BUG #19095: Test if function exit() is used fail when linked static

From 6ba784e27f6d2a7023828263f988b7a2716fe614 Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Tue, 11 Nov 2025 17:36:29 +0530
Subject: [PATCH] Fix: prevent false exit() match in libpq static link check

The previous Makefile check used 'grep exit', which also matched
symbols like 'atexit' and 'OPENSSL_atexit' from libcrypto.a.
This caused false positive link failures when statically linking
libpq with OpenSSL.

Use 'grep -x exit' to match only the exact symbol name.

Signed-off-by: BharatDBPG <bharatdbpg@gmail.com>
---
 src/interfaces/libpq/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da66500..8cff30b 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -144,7 +144,7 @@ $(stlib): $(OBJS_STATIC)
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
+	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep -x exit; then \
 		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
 	fi
 endif
-- 
2.43.0

From 6ba784e27f6d2a7023828263f988b7a2716fe614 Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Tue, 11 Nov 2025 17:36:29 +0530
Subject: [PATCH] Fix: prevent false exit() match in libpq static link check

The previous Makefile check used 'grep exit', which also matched
symbols like 'atexit' and 'OPENSSL_atexit' from libcrypto.a.
This caused false positive link failures when statically linking
libpq with OpenSSL.

Use 'grep -x exit' to match only the exact symbol name.

Signed-off-by: BharatDBPG <bharatdbpg@gmail.com>
---
 src/interfaces/libpq/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da66500..8cff30b 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -144,7 +144,7 @@ $(stlib): $(OBJS_STATIC)
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
+	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep -x exit; then \
 		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
 	fi
 endif
-- 
2.43.0

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da6650066d4..3bd0e4f3840 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -144,7 +144,7 @@ $(stlib): $(OBJS_STATIC)
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
+	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit -e pthread_exit | grep exit; then \
 		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
 	fi
 endif

From f711555fd2b69e74a33312f5ba8750b8fec97f1f Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Wed, 19 Nov 2025 12:17:43 +0530
Subject: [PATCH] libpq: Add exit() function check for Meson build and
 whitelist pthread_exit()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The Makefile-based build already performs a safety check to ensure that
libpq does not accidentally reference exit() or related termination
functions.

Meson, however, did not run this check. As a result, Meson builds could
miss accidental references to exit()-family functions which ideally
should never be called inside libpq.

This patch adds the missing scan to the Meson build by:
  • Scanning the libpq .o files using nm and filtering through the same
    whitelist logic as the Makefile.
  • Adding pthread_exit() to the Meson whitelist, matching the behavior
    of the existing Makefile check.

With this change, both Makefile and Meson builds apply the same
validation for unwanted exit() usage.

Signed-off-by: Vasuki[BharatDBPG] <bharatdbpg@gmail.com>
---
 meson.build                      |  1 +
 src/interfaces/libpq/Makefile    |  7 ++--
 src/interfaces/libpq/meson.build | 70 +++++++++++++++-----------------
 3 files changed, 37 insertions(+), 41 deletions(-)

diff --git a/meson.build b/meson.build
index 24aeffe..e20bfe6 100644
--- a/meson.build
+++ b/meson.build
@@ -3812,6 +3812,7 @@ alias_target('bin', bin_targets + [libpq_st])
 alias_target('pl', pl_targets)
 alias_target('contrib', contrib_targets)
 alias_target('testprep', testprep_targets)
+alias_target('run-check-libpq', [check_exit_target])
 
 alias_target('world', all_built, docs)
 alias_target('install-world', install_quiet, installdocs)
diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index 3bd0e4f..1ad3c60 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -134,9 +134,10 @@ $(stlib): $(OBJS_STATIC)
 # build toolchains insert abort() calls, e.g. to implement assert().)
 # If nm doesn't exist or doesn't work on shlibs, this test will do nothing,
 # which is fine.  The exclusion of __cxa_atexit is necessary on OpenBSD,
-# which seems to insert references to that even in pure C code. Excluding
-# __tsan_func_exit is necessary when using ThreadSanitizer data race detector
-# which use this function for instrumentation of function exit.
+# which seems to insert references to that even in pure C code.  Excluding
+# __tsan_func_exit is necessary when using ThreadSanitizer, which emits this
+# symbol as part of its instrumentation of function exits.  Excluding
+# pthread_exit allows legitimate thread shutdown paths used on some builds.
 # Skip the test when profiling, as gcc may insert exit() calls for that.
 # Also skip the test on platforms where libpq infrastructure may be provided
 # by statically-linked libraries, as we can't expect them to honor this
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index 4b1e8a2..4822814 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -1,5 +1,4 @@
 # Copyright (c) 2022-2025, PostgreSQL Global Development Group
-
 libpq_sources = files(
   'fe-auth-oauth.c',
   'fe-auth-scram.c',
@@ -85,6 +84,38 @@ libpq = declare_dependency(
   include_directories: [include_directories('.')]
 )
 
+# Sanity check to ensure libpq does not contain any unintended references
+# to exit() in its object files.  Client libraries must not terminate the
+# calling process, so we scan all libpq .o files with 'nm' and fail the
+# build if a direct exit() reference is found.  Certain harmless symbols
+# (__cxa_atexit, __tsan_func_exit, pthread_exit) are whitelisted.
+# Skip on cross-builds, sanitizer coverage, and Windows
+
+if not meson.is_cross_build() and not get_option('b_coverage') and host_system != 'windows'
+  check_exit_target = custom_target(
+    'check-libpq-no-exit',
+    output: 'libpq-nm-stamp',
+    depends: [libpq_st, libpq_so],
+    build_by_default: true,
+    command: [
+      'bash','-eu', '-c',
+      '''
+      echo "Checking that libpq object files do not reference exit()..."  
+      obj_files=$(find src/interfaces/libpq -type f -name "*.o")
+      for f in $obj_files; do
+        if nm -u "$f" 2>/dev/null \
+            | grep -v -E '__cxa_atexit|__tsan_func_exit|pthread_exit' \
+            | grep exit; then
+          echo "ERROR: exit()-related reference found in: $f"
+          exit 1
+        fi
+      done            
+      touch  @OUTPUT@
+      '''.format(meson.current_build_dir())
+    ],
+  )
+
+endif
 
 private_deps = [
   frontend_stlib_code,
@@ -147,41 +178,4 @@ tests += {
   },
 }
 
-# Verify that libpq does not reference functions that may invoke exit().
-#
-# This check parallels the Makefile logic used in the autoconf build system.
-# 
-# The following symbols are considered safe and therefore ignored:
-#   - __cxa_atexit      : used for C++ static destructors
-#   - __tsan_func_exit  : thread sanitizer instrumentation
-#   - pthread_exit      : used by thread runtimes, harmless here
-#
-# The test runs only for native builds (not cross-builds) and when code
-# coverage is disable
-
-if not meson.is_cross_build() and not get_option('b_coverage') and host_system != 'sunos'
-  check_exit_target = custom_target(
-    'check-libpq-no-exit',
-    output: 'libpq-refs-stamp',
-    depends: libpq_so,
-    build_by_default: true,
-    command: [
-      'bash', '-c',
-      '''
-      echo "Running exit() reference check for libpq..."
-      if nm -A -u @0@ 2>/dev/null | \
-         grep -v -e __cxa_atexit -e __tsan_func_exit -e pthread_exit | \
-         grep exit; then
-         echo "ERROR: libpq must not be calling any function which invokes exit()"
-         exit 1
-      else
-         echo "SUCCESS: No exit() references found in libpq"
-      fi
-      '''.format(libpq_so.full_path())
-    ],
-    build_always_stale: true,
-    capture: false
-  )
-endif
-
 subdir('po', if_found: libintl)
-- 
2.43.0

From f0679266bda765f4e1e15bfee97d2817d3bd78ea Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Wed, 19 Nov 2025 17:43:53 +0530
Subject: [PATCH] libpq: Add exit() function check for Meson build and
 whitelist pthread_exit()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The Makefile-based build already performs a safety check to ensure that
libpq does not accidentally reference exit() or related termination
functions.

Meson, however, did not run this check. As a result, Meson builds could
miss accidental references to exit()-family functions which ideally
should never be called inside libpq.

This patch adds the missing scan to the Meson build by:
  • Scanning the libpq .o files using nm and filtering through the same
    whitelist logic as the Makefile.
  • Adding pthread_exit() to the Meson whitelist, matching the behavior
    of the existing Makefile check.

With this change, both Makefile and Meson builds apply the same
validation for unwanted exit() usage.
---
 meson.build                      |  1 +
 src/interfaces/libpq/Makefile    |  5 +++--
 src/interfaces/libpq/meson.build | 30 ++++++++++++++++++++++++++++++
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/meson.build b/meson.build
index c1e17aa3040..47588ead9fb 100644
--- a/meson.build
+++ b/meson.build
@@ -3820,6 +3820,7 @@ alias_target('bin', bin_targets + [libpq_st])
 alias_target('pl', pl_targets)
 alias_target('contrib', contrib_targets)
 alias_target('testprep', testprep_targets)
+alias_target('run-check-libpq', [check_exit_target])
 
 alias_target('world', all_built, docs)
 alias_target('install-world', install_quiet, installdocs)
diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da6650066d4..7b20d84d51d 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -137,14 +137,15 @@ $(stlib): $(OBJS_STATIC)
 # which seems to insert references to that even in pure C code. Excluding
 # __tsan_func_exit is necessary when using ThreadSanitizer data race detector
 # which use this function for instrumentation of function exit.
-# Skip the test when profiling, as gcc may insert exit() calls for that.
+#Excluding pthread_exit allows legitimate thread shutdown paths used on some builds.
+#Skip the test when profiling, as gcc may insert exit() calls for that.
 # Also skip the test on platforms where libpq infrastructure may be provided
 # by statically-linked libraries, as we can't expect them to honor this
 # coding rule.
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
+	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit -e pthread_exit | grep exit; then \
 		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
 	fi
 endif
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index a74e885b169..30324731e9c 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -85,6 +85,36 @@ libpq = declare_dependency(
   include_directories: [include_directories('.')]
 )
 
+# Sanity check to ensure libpq does not contain any unintended references
+# to exit() in its object files.  Client libraries must not terminate the
+# calling process, so we scan all libpq .o files with 'nm' and fail the
+# build if a direct exit() reference is found.  Certain harmless symbols
+# (__cxa_atexit, __tsan_func_exit, pthread_exit) are whitelisted.
+# Skip on cross-builds, sanitizer coverage, and Windows
+
+if not meson.is_cross_build() and not get_option('b_coverage') and host_system != 'windows'
+  check_exit_target = custom_target(
+    'check-libpq-no-exit',
+    output: 'libpq-nm-stamp',
+    depends: [libpq_st, libpq_so],
+    build_by_default: true,
+    command: [
+      'bash','-eu', '-c',
+      '''
+      echo "Checking that libpq object files do not reference exit()..."
+      obj_files=$(find src/interfaces/libpq -type f -name "*.o")
+      for f in $obj_files; do
+        if nm -u "$f" 2>/dev/null| grep -v -E '__cxa_atexit|__tsan_func_exit|pthread_exit'| grep exit; then
+          echo "ERROR: exit()-related reference found in: $f"
+          exit 1
+        fi
+      done
+      touch  @OUTPUT@
+      '''.format(meson.current_build_dir())
+    ],
+  )
+
+endif
 private_deps = [
   frontend_stlib_code,
   libpq_deps,
-- 
2.43.0

From 63a503dc5a3963b0e45e3634495563e52181bf23 Mon Sep 17 00:00:00 2001
From: Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: Wed, 19 Nov 2025 12:08:08 +0300
Subject: [PATCH v1] Add exit() check for libpq.so for meson build

---
 src/interfaces/libpq/Makefile         |  4 +-
 src/interfaces/libpq/libpq-exit-check | 71 +++++++++++++++++++++++++++
 src/interfaces/libpq/meson.build      | 27 ++++++++++
 3 files changed, 99 insertions(+), 3 deletions(-)
 create mode 100755 src/interfaces/libpq/libpq-exit-check

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da6650066d4..6b2d1769a07 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -144,9 +144,7 @@ $(stlib): $(OBJS_STATIC)
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
-		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
-	fi
+	$(PERL) libpq-exit-check --input_file $<
 endif
 endif
 	touch $@
diff --git a/src/interfaces/libpq/libpq-exit-check b/src/interfaces/libpq/libpq-exit-check
new file mode 100755
index 00000000000..84fa2a7fbe0
--- /dev/null
+++ b/src/interfaces/libpq/libpq-exit-check
@@ -0,0 +1,71 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings FATAL => 'all';
+
+use Getopt::Long;
+
+my $input_file;
+my $stamp_file;
+my @problematic_lines;
+
+GetOptions(
+	'input_file:s' => \$input_file,
+	'stamp_file:s' => \$stamp_file) or die "$0: wrong arguments";
+
+die "$0: --input_file must be specified\n" unless defined $input_file;
+
+open my $fh, '-|', "nm -A -u $input_file 2>/dev/null"
+  or die "Cannot run nm: $!";
+
+while (<$fh>)
+{
+	next if /__cxa_atexit/;
+	next if /__tsan_func_exit/;
+    next if /pthread_exit/;
+
+	if (/exit/)
+	{
+		push @problematic_lines, $_;
+	}
+}
+
+if (@problematic_lines)
+{
+	remove_stamp_file();
+
+	print "libpq must not be calling any function which invokes exit\n";
+	print "Problematic symbol references:\n";
+	print @problematic_lines;
+
+	exit 1;
+}
+else
+{
+	# All checks are passed, we can create a stamp file meson build now
+	if ($stamp_file)
+	{
+		create_stamp_file();
+	}
+
+	exit 0;
+}
+
+sub create_stamp_file
+{
+	# Avoid touching existing stamp file to prevent unnecessary rebuilds
+	if (!(-f $stamp_file))
+	{
+		open my $fh, '>', $stamp_file
+		  or die "can't open $stamp_file: $!";
+		close $fh;
+	}
+}
+
+sub remove_stamp_file
+{
+	if ($stamp_file)
+	{
+		unlink $stamp_file;
+	}
+}
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index a74e885b169..978fff192ea 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -80,6 +80,33 @@ libpq_so = shared_library('libpq',
   kwargs: default_lib_args,
 )
 
+# Check for functions that libpq must not call, currently just exit().
+# (Ideally we'd reject abort() too, but there are various scenarios where
+# build toolchains insert abort() calls, e.g. to implement assert().)
+# If nm doesn't exist or doesn't work on shlibs, this test will do nothing,
+# which is fine.  The exclusion of __cxa_atexit is necessary on OpenBSD,
+# which seems to insert references to that even in pure C code. Excluding
+# __tsan_func_exit is necessary when using ThreadSanitizer data race detector
+# which use this function for instrumentation of function exit.
+# Skip the test when profiling, as gcc may insert exit() calls for that.
+# Also skip the test on platforms where libpq infrastructure may be provided
+# by statically-linked libraries, as we can't expect them to honor this
+# coding rule.
+if find_program('nm', required: false, native: true).found() and portname != 'solaris' and not get_option('b_coverage')
+  custom_target(
+    'libpq-exit-check',
+    input: libpq_so,
+    output: 'libpq-refs-stamp',
+    command: [
+      perl,
+        files('libpq-exit-check'),
+          '--input_file', '@INPUT@',
+          '--stamp_file', '@OUTPUT@'
+    ],
+    build_by_default: true,
+  )
+endif
+
 libpq = declare_dependency(
   link_with: [libpq_so],
   include_directories: [include_directories('.')]
-- 
2.51.0

From 21ae5e54a73d4ea98c91ad4de38afe90c80042b7 Mon Sep 17 00:00:00 2001
From: Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: Wed, 19 Nov 2025 12:08:08 +0300
Subject: [PATCH v2] Add exit() check for libpq.so for meson build

---
 src/interfaces/libpq/Makefile         |  4 +-
 src/interfaces/libpq/libpq-exit-check | 61 +++++++++++++++++++++++++++
 src/interfaces/libpq/meson.build      | 27 ++++++++++++
 3 files changed, 89 insertions(+), 3 deletions(-)
 create mode 100755 src/interfaces/libpq/libpq-exit-check

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da6650066d4..6b2d1769a07 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -144,9 +144,7 @@ $(stlib): $(OBJS_STATIC)
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
 ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
-		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
-	fi
+	$(PERL) libpq-exit-check --input_file $<
 endif
 endif
 	touch $@
diff --git a/src/interfaces/libpq/libpq-exit-check b/src/interfaces/libpq/libpq-exit-check
new file mode 100755
index 00000000000..e3c2a6e768d
--- /dev/null
+++ b/src/interfaces/libpq/libpq-exit-check
@@ -0,0 +1,61 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings FATAL => 'all';
+
+use Getopt::Long;
+
+my $input_file;
+my $stamp_file;
+my @problematic_lines;
+
+GetOptions(
+	'input_file:s' => \$input_file,
+	'stamp_file:s' => \$stamp_file) or die "$0: wrong arguments";
+
+die "$0: --input_file must be specified\n" unless defined $input_file;
+
+open my $fh, '-|', "nm -A -u $input_file 2>/dev/null"
+  or die "Cannot run nm: $!";
+
+while (<$fh>)
+{
+	next if /__cxa_atexit/;
+	next if /__tsan_func_exit/;
+	next if /pthread_exit/;
+
+	if (/exit/)
+	{
+		push @problematic_lines, $_;
+	}
+}
+
+if (@problematic_lines)
+{
+	print "libpq must not be calling any function which invokes exit\n";
+	print "Problematic symbol references:\n";
+	print @problematic_lines;
+
+	exit 1;
+}
+else
+{
+	# All checks are passed, we can create a stamp file meson build now
+	if ($stamp_file)
+	{
+		create_stamp_file();
+	}
+
+	exit 0;
+}
+
+sub create_stamp_file
+{
+	# Avoid touching existing stamp file to prevent unnecessary rebuilds
+	if (!(-f $stamp_file))
+	{
+		open my $fh, '>', $stamp_file
+		  or die "can't open $stamp_file: $!";
+		close $fh;
+	}
+}
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index a74e885b169..978fff192ea 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -80,6 +80,33 @@ libpq_so = shared_library('libpq',
   kwargs: default_lib_args,
 )
 
+# Check for functions that libpq must not call, currently just exit().
+# (Ideally we'd reject abort() too, but there are various scenarios where
+# build toolchains insert abort() calls, e.g. to implement assert().)
+# If nm doesn't exist or doesn't work on shlibs, this test will do nothing,
+# which is fine.  The exclusion of __cxa_atexit is necessary on OpenBSD,
+# which seems to insert references to that even in pure C code. Excluding
+# __tsan_func_exit is necessary when using ThreadSanitizer data race detector
+# which use this function for instrumentation of function exit.
+# Skip the test when profiling, as gcc may insert exit() calls for that.
+# Also skip the test on platforms where libpq infrastructure may be provided
+# by statically-linked libraries, as we can't expect them to honor this
+# coding rule.
+if find_program('nm', required: false, native: true).found() and portname != 'solaris' and not get_option('b_coverage')
+  custom_target(
+    'libpq-exit-check',
+    input: libpq_so,
+    output: 'libpq-refs-stamp',
+    command: [
+      perl,
+        files('libpq-exit-check'),
+          '--input_file', '@INPUT@',
+          '--stamp_file', '@OUTPUT@'
+    ],
+    build_by_default: true,
+  )
+endif
+
 libpq = declare_dependency(
   link_with: [libpq_so],
   include_directories: [include_directories('.')]
-- 
2.51.0

From 2a8d4a7defe43a31e32dae2d32e7db978cd11739 Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Tue, 25 Nov 2025 12:33:53 +0530
Subject: [PATCH v3] libpq: centralize exit() check logic in Perl script and
 share with Meson and Makefile

The existing Makefile-based build performs a safety check to ensure that
libpq does not accidentally reference exit(), since client libraries
must not terminate the calling process. Meson builds did not run an
equivalent check, and the logic for platform-specific handling and
whitelisting was duplicated in the Makefile comments.

This patch introduces a new helper script, src/interfaces/libpq/libpq-exit-check,
and makes both the Makefile and Meson builds invoke it:

  * Move the exit() checking logic into libpq-exit-check, written in Perl.
    The script calls nm on the given library, filters out known harmless
    symbols (__cxa_atexit, __tsan_func_exit, pthread_exit), and reports
    any remaining exit()-related references.

  * Centralize platform-specific behavior inside the script:
      - Skip the check on Solaris, where libpq infrastructure may come
        from statically-linked libraries.
      - Skip the check entirely when nm is not found or is not usable.
    This removes the need for separate Solaris checks and detailed
    comments in the Makefile and Meson files.

  * Reduce the Makefile and Meson-side logic to a simple invocation of
    libpq-exit-check plus a brief comment that the platform rules live
    in the script. Meson uses a custom_target with a stamp file so the
    check only reruns when libpq.so is rebuilt.

With these changes, both autoconf/Makefile and Meson builds enforce the
same exit() policy for libpq while keeping the implementation and
platform rules in a single place.
---
 src/interfaces/libpq/Makefile         | 20 +-----
 src/interfaces/libpq/libpq-exit-check | 98 +++++++++++++++++++++++++++
 src/interfaces/libpq/meson.build      | 17 +++++
 3 files changed, 118 insertions(+), 17 deletions(-)
 create mode 100755 src/interfaces/libpq/libpq-exit-check

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da66500..305361f 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -130,26 +130,12 @@ $(stlib): override OBJS += $(OBJS_STATIC)
 $(stlib): $(OBJS_STATIC)
 
 # Check for functions that libpq must not call, currently just exit().
-# (Ideally we'd reject abort() too, but there are various scenarios where
-# build toolchains insert abort() calls, e.g. to implement assert().)
-# If nm doesn't exist or doesn't work on shlibs, this test will do nothing,
-# which is fine.  The exclusion of __cxa_atexit is necessary on OpenBSD,
-# which seems to insert references to that even in pure C code. Excluding
-# __tsan_func_exit is necessary when using ThreadSanitizer data race detector
-# which use this function for instrumentation of function exit.
-# Skip the test when profiling, as gcc may insert exit() calls for that.
-# Also skip the test on platforms where libpq infrastructure may be provided
-# by statically-linked libraries, as we can't expect them to honor this
-# coding rule.
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
-ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
-		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
-	fi
+    # See libpq-exit-check for full platform rules and whitelisting.
+    $(PERL) libpq-exit-check --input_file $<
 endif
-endif
-	touch $@
+    touch $@
 
 # Make dependencies on pg_config_paths.h visible in all builds.
 fe-connect.o: fe-connect.c $(top_builddir)/src/port/pg_config_paths.h
diff --git a/src/interfaces/libpq/libpq-exit-check b/src/interfaces/libpq/libpq-exit-check
new file mode 100755
index 0000000..f500cef
--- /dev/null
+++ b/src/interfaces/libpq/libpq-exit-check
@@ -0,0 +1,98 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings FATAL => 'all';
+
+use Getopt::Long;
+use Config;
+
+#
+# Platform & tool notes:
+#
+# - Purpose: ensure libpq never references exit(), because client libraries
+#   must not terminate the host application.
+#
+# - Whitelisted injected symbols:
+#       __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
+#       __tsan_func_exit - ThreadSanitizer instrumentation
+#       pthread_exit     - legitimate thread cleanup
+#
+# - Solaris: libpq infrastructure may be statically linked -> skip check.
+#
+# - nm availability:
+#       If nm does not exist or cannot be executed, skip the scan.
+#       This matches PostgreSQL behavior in Makefile builds.
+#
+# - Makefile and Meson both rely on this script for full logic.
+#
+
+my $input_file;
+my $stamp_file;
+my @problematic_lines;
+
+Getopt::Long::GetOptions(
+    'input_file:s' => \$input_file,
+    'stamp_file:s' => \$stamp_file) or die "$0: wrong arguments\n";
+
+die "$0: --input_file must be specified\n" unless defined $input_file;
+
+# ---- Skip entirely on Solaris ----
+if ($Config{osname} =~ /solaris/i) {
+    exit 0;
+}
+
+# ---- Check if 'nm' exists on the system ----
+my $nm_path = `which nm 2>/dev/null`;
+chomp($nm_path);
+
+if (!$nm_path || ! -x $nm_path) {
+    # nm not available → skip check gracefully
+    exit 0;
+}
+
+# ---- Run nm to scan undefined symbols ----
+open my $fh, '-|', "$nm_path -A -u $input_file 2>/dev/null"
+    or exit 0;  # If nm fails at runtime, skip also
+
+while (<$fh>)
+{
+    # Allowed symbols
+    next if /__cxa_atexit/;
+    next if /__tsan_func_exit/;
+    next if /pthread_exit/;
+
+    # Anything containing "exit" is suspicious
+    if (/exit/)
+    {
+        push @problematic_lines, $_;
+    }
+}
+
+if (@problematic_lines)
+{
+    print "libpq must not be calling any function which invokes exit\n";
+    print "Problematic symbol references:\n";
+    print @problematic_lines;
+
+    exit 1;
+}
+else
+{
+    # Meson optional stamp file
+    if ($stamp_file)
+    {
+        create_stamp_file();
+    }
+
+    exit 0;
+}
+
+sub create_stamp_file
+{
+    if (!(-f $stamp_file))
+    {
+        open my $fh, '>', $stamp_file
+            or die "can't open $stamp_file: $!";
+        close $fh;
+    }
+}
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index a74e885..1b32eed 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -85,6 +85,23 @@ libpq = declare_dependency(
   include_directories: [include_directories('.')]
 )
 
+# Run the unified exit() check script for libpq.
+# All platform-specific rules are implemented inside libpq-exit-check.
+if find_program('nm', required: false, native: true).found() and not get_option('b_coverage')
+  custom_target(
+    'libpq-exit-check',
+    input: libpq_so,
+    output: 'libpq-refs-stamp',
+    command: [
+      perl,
+        files('libpq-exit-check'),
+          '--input_file', '@INPUT@',
+          '--stamp_file', '@OUTPUT@'
+    ],
+    build_by_default: true,
+  )
+endif
+
 private_deps = [
   frontend_stlib_code,
   libpq_deps,
-- 
2.43.0

From 89f4c76703ac1b50e8ee9bea6045757187f35e81 Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Wed, 3 Dec 2025 17:18:56 +0530
Subject: [PATCH v4] libpq: centralize exit() check logic and unify
 Makefile/Meson behavior

Move the libpq exit() reference check into a shared Perl script
(libpq-exit-check) and use it for both autoconf/Makefile and Meson
builds.  This avoids duplicated logic and ensures consistent
platform-specific handling of whitelisted symbols.

The script now receives the full path to `nm`, detected at the
top-level configure using AC_PATH_PROG and propagated via NM_PROG.
Both Makefile and Meson invoke the script with --nm=<path>.

Platform-specific behavior (Solaris skip, Windows skip, whitelisted
symbols, nm availability checks) is centralized inside the script.

This makes the two build systems apply the same exit() policy and keeps
all rules in one place.
---
 configure.ac                          |   2 +
 meson.build                           |   1 +
 src/Makefile.global.in                |   2 +-
 src/interfaces/libpq/Makefile         |   9 ++-
 src/interfaces/libpq/libpq-exit-check | 100 ++++++++++++--------------
 src/interfaces/libpq/meson.build      |  10 ++-
 6 files changed, 62 insertions(+), 62 deletions(-)

diff --git a/configure.ac b/configure.ac
index c241372..7284f1f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1214,6 +1214,8 @@ case $MKDIR_P in
   *install-sh*) MKDIR_P='\${SHELL} \${top_srcdir}/config/install-sh -c -d';;
 esac
 
+AC_PATH_PROG(NM, nm)
+AC_SUBST(NM)
 PGAC_PATH_BISON
 PGAC_PATH_FLEX
 
diff --git a/meson.build b/meson.build
index c1e17aa..273cb1f 100644
--- a/meson.build
+++ b/meson.build
@@ -350,6 +350,7 @@ missing = find_program('config/missing', native: true)
 cp = find_program('cp', required: false, native: true)
 xmllint_bin = find_program(get_option('XMLLINT'), native: true, required: false)
 xsltproc_bin = find_program(get_option('XSLTPROC'), native: true, required: false)
+nm = find_program('nm', required: false, native: true)
 
 bison_flags = []
 if bison.found()
diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 0aa389b..9d12cdb 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -285,7 +285,7 @@ LLVM_CFLAGS = @LLVM_CFLAGS@
 LLVM_CXXFLAGS = @LLVM_CXXFLAGS@
 
 # Kind-of compilers
-
+NM = @NM@
 BISON = @BISON@
 BISONFLAGS = @BISONFLAGS@ $(YFLAGS)
 FLEX = @FLEX@
diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index 305361f..6e1fb30 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -130,12 +130,15 @@ $(stlib): override OBJS += $(OBJS_STATIC)
 $(stlib): $(OBJS_STATIC)
 
 # Check for functions that libpq must not call, currently just exit().
+# (Ideally we'd reject abort() too, but there are various scenarios where
+# build toolchains insert abort() calls, e.g. to implement assert().)
+# Skip the test when profiling, as gcc may insert exit() calls for that.
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
-    # See libpq-exit-check for full platform rules and whitelisting.
-    $(PERL) libpq-exit-check --input_file $<
+# See libpq-exit-check for full platform rules and whitelisting.
+	$(PERL) libpq-exit-check --input_file $< --nm='$(NM)'
 endif
-    touch $@
+	touch $@
 
 # Make dependencies on pg_config_paths.h visible in all builds.
 fe-connect.o: fe-connect.c $(top_builddir)/src/port/pg_config_paths.h
diff --git a/src/interfaces/libpq/libpq-exit-check b/src/interfaces/libpq/libpq-exit-check
index f500cef..bfac4ca 100755
--- a/src/interfaces/libpq/libpq-exit-check
+++ b/src/interfaces/libpq/libpq-exit-check
@@ -6,93 +6,83 @@ use warnings FATAL => 'all';
 use Getopt::Long;
 use Config;
 
-#
-# Platform & tool notes:
-#
 # - Purpose: ensure libpq never references exit(), because client libraries
 #   must not terminate the host application.
-#
-# - Whitelisted injected symbols:
-#       __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
-#       __tsan_func_exit - ThreadSanitizer instrumentation
-#       pthread_exit     - legitimate thread cleanup
-#
-# - Solaris: libpq infrastructure may be statically linked -> skip check.
-#
-# - nm availability:
-#       If nm does not exist or cannot be executed, skip the scan.
-#       This matches PostgreSQL behavior in Makefile builds.
-#
 # - Makefile and Meson both rely on this script for full logic.
-#
 
+my $nm_path;
 my $input_file;
 my $stamp_file;
 my @problematic_lines;
 
 Getopt::Long::GetOptions(
-    'input_file:s' => \$input_file,
-    'stamp_file:s' => \$stamp_file) or die "$0: wrong arguments\n";
+	'nm:s' => \$nm_path,
+	'input_file:s' => \$input_file,
+	'stamp_file:s' => \$stamp_file) or die "$0: wrong arguments\n";
 
 die "$0: --input_file must be specified\n" unless defined $input_file;
+die "$0: --nm must be specified\n" unless defined $nm_path and -x $nm_path;
 
-# ---- Skip entirely on Solaris ----
-if ($Config{osname} =~ /solaris/i) {
-    exit 0;
+# ---- Skip Windows ----
+if ($Config{osname} =~ /MSWin32|cygwin|msys/i)
+{
+	exit 0;
 }
 
-# ---- Check if 'nm' exists on the system ----
-my $nm_path = `which nm 2>/dev/null`;
-chomp($nm_path);
-
-if (!$nm_path || ! -x $nm_path) {
-    # nm not available → skip check gracefully
-    exit 0;
+# ---- Skip entirely on Solaris ----
+if ($Config{osname} =~ /solaris/i)
+{
+	exit 0;
 }
 
 # ---- Run nm to scan undefined symbols ----
 open my $fh, '-|', "$nm_path -A -u $input_file 2>/dev/null"
-    or exit 0;  # If nm fails at runtime, skip also
+  or exit 0;    # If nm fails at runtime, skip also
 
 while (<$fh>)
 {
-    # Allowed symbols
-    next if /__cxa_atexit/;
-    next if /__tsan_func_exit/;
-    next if /pthread_exit/;
-
-    # Anything containing "exit" is suspicious
-    if (/exit/)
-    {
-        push @problematic_lines, $_;
-    }
+	# Whitelisted injected symbols:
+	#     __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
+	#     __tsan_func_exit - ThreadSanitizer instrumentation
+	#     pthread_exit     - legitimate thread cleanup
+
+	next if /__cxa_atexit/;
+	next if /__tsan_func_exit/;
+	next if /pthread_exit/;
+
+	# Anything containing "exit" is suspicious
+	if (/exit/)
+	{
+		push @problematic_lines, $_;
+	}
 }
+close $fh;
 
 if (@problematic_lines)
 {
-    print "libpq must not be calling any function which invokes exit\n";
-    print "Problematic symbol references:\n";
-    print @problematic_lines;
+	print "libpq must not be calling any function which invokes exit\n";
+	print "Problematic symbol references:\n";
+	print @problematic_lines;
 
-    exit 1;
+	exit 1;
 }
 else
 {
-    # Meson optional stamp file
-    if ($stamp_file)
-    {
-        create_stamp_file();
-    }
+	# Meson optional stamp file
+	if ($stamp_file)
+	{
+		create_stamp_file();
+	}
 
-    exit 0;
+	exit 0;
 }
 
 sub create_stamp_file
 {
-    if (!(-f $stamp_file))
-    {
-        open my $fh, '>', $stamp_file
-            or die "can't open $stamp_file: $!";
-        close $fh;
-    }
+	if (!(-f $stamp_file))
+	{
+		open my $fh, '>', $stamp_file
+		  or die "can't open $stamp_file: $!";
+		close $fh;
+	}
 }
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index 1b32eed..6f97f49 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -85,9 +85,12 @@ libpq = declare_dependency(
   include_directories: [include_directories('.')]
 )
 
-# Run the unified exit() check script for libpq.
+# Check for functions that libpq must not call, currently just exit().
+# (Ideally we'd reject abort() too, but there are various scenarios where
+# build toolchains insert abort() calls, e.g. to implement assert().)
+# Skip the test when profiling, as gcc may insert exit() calls for that.
 # All platform-specific rules are implemented inside libpq-exit-check.
-if find_program('nm', required: false, native: true).found() and not get_option('b_coverage')
+if nm.found() and not get_option('b_coverage')
   custom_target(
     'libpq-exit-check',
     input: libpq_so,
@@ -96,7 +99,8 @@ if find_program('nm', required: false, native: true).found() and not get_option(
       perl,
         files('libpq-exit-check'),
           '--input_file', '@INPUT@',
-          '--stamp_file', '@OUTPUT@'
+          '--stamp_file', '@OUTPUT@',
+	  '--nm', nm.full_path()
     ],
     build_by_default: true,
   )
-- 
2.43.0

From 43a7099781d13b1ccd119acf955b8dce6fa0c279 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Thu, 4 Dec 2025 09:12:58 +0900
Subject: [PATCH v5 1/2] libpq: centralize exit() check logic and unify
 Makefile/Meson behavior

Move the libpq exit() reference check into a shared Perl script
(libpq-exit-check) and use it for both autoconf/Makefile and Meson
builds.  This avoids duplicated logic and ensures consistent
platform-specific handling of whitelisted symbols.

The script now receives the full path to `nm`, detected at the
top-level configure using AC_PATH_PROG and propagated via NM_PROG.
Both Makefile and Meson invoke the script with --nm=<path>.

Platform-specific behavior (Solaris skip, Windows skip, whitelisted
symbols, nm availability checks) is centralized inside the script.

This makes the two build systems apply the same exit() policy and keeps
all rules in one place.
---
 src/interfaces/libpq/Makefile       | 21 ++-----
 src/interfaces/libpq/libpq-check.pl | 86 +++++++++++++++++++++++++++++
 src/interfaces/libpq/meson.build    | 19 +++++++
 configure                           | 42 ++++++++++++++
 configure.ac                        |  2 +
 meson.build                         |  1 +
 src/Makefile.global.in              |  1 +
 7 files changed, 155 insertions(+), 17 deletions(-)
 create mode 100755 src/interfaces/libpq/libpq-check.pl

diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da6650066d46..1b7d3ecf8aac 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -129,25 +129,12 @@ $(shlib): $(OBJS_SHLIB)
 $(stlib): override OBJS += $(OBJS_STATIC)
 $(stlib): $(OBJS_STATIC)
 
-# Check for functions that libpq must not call, currently just exit().
-# (Ideally we'd reject abort() too, but there are various scenarios where
-# build toolchains insert abort() calls, e.g. to implement assert().)
-# If nm doesn't exist or doesn't work on shlibs, this test will do nothing,
-# which is fine.  The exclusion of __cxa_atexit is necessary on OpenBSD,
-# which seems to insert references to that even in pure C code. Excluding
-# __tsan_func_exit is necessary when using ThreadSanitizer data race detector
-# which use this function for instrumentation of function exit.
-# Skip the test when profiling, as gcc may insert exit() calls for that.
-# Also skip the test on platforms where libpq infrastructure may be provided
-# by statically-linked libraries, as we can't expect them to honor this
-# coding rule.
+# Check for functions that libpq must not call.  See libpq-check.pl for the
+# full set of platform rules.  Skip the test when profiling, as gcc may
+# insert exit() calls for that.
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
-ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
-		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
-	fi
-endif
+	$(PERL) libpq-check.pl --input_file $< --nm='$(NM)'
 endif
 	touch $@
 
diff --git a/src/interfaces/libpq/libpq-check.pl b/src/interfaces/libpq/libpq-check.pl
new file mode 100755
index 000000000000..274e873d1fca
--- /dev/null
+++ b/src/interfaces/libpq/libpq-check.pl
@@ -0,0 +1,86 @@
+#!/usr/bin/perl
+#
+# src/interfaces/libpq/libpq-check.pl
+#
+# Copyright (c) 2025, PostgreSQL Global Development Group
+#
+# Check that the state of a libpq library.  Currently, this script checks
+# that exit() is not called, because client libraries must not terminate
+# the host application.
+#
+# This script is called by both Makefile and Meson.
+
+use strict;
+use warnings FATAL => 'all';
+
+use Getopt::Long;
+use Config;
+
+my $nm_path;
+my $input_file;
+my $stamp_file;
+my @problematic_lines;
+
+Getopt::Long::GetOptions(
+	'nm:s' => \$nm_path,
+	'input_file:s' => \$input_file,
+	'stamp_file:s' => \$stamp_file) or die "$0: wrong arguments\n";
+
+die "$0: --input_file must be specified\n" unless defined $input_file;
+die "$0: --nm must be specified\n" unless defined $nm_path and -x $nm_path;
+
+sub create_stamp_file
+{
+	if (!(-f $stamp_file))
+	{
+		open my $fh, '>', $stamp_file
+		  or die "can't open $stamp_file: $!";
+		close $fh;
+	}
+}
+
+# ---- Skip on Windows and Solaris ----
+if (   $Config{osname} =~ /MSWin32|cygwin|msys/i
+	|| $Config{osname} =~ /solaris/i)
+{
+	exit 0;
+}
+
+# Run nm to scan for symbols.  If nm fails at runtime, skip the check.
+open my $fh, '-|', "$nm_path -A -u $input_file 2>/dev/null"
+  or exit 0;
+
+while (<$fh>)
+{
+	# Set of symbols allowed:
+	#     __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
+	#     __tsan_func_exit - ThreadSanitizer instrumentation
+
+	next if /__cxa_atexit/;
+	next if /__tsan_func_exit/;
+
+	# Anything containing "exit" is suspicious.
+	# (Ideally we should reject abort() too, but there are various scenarios
+	# where build toolchains insert abort() calls, e.g. to implement assert().)
+	if (/exit/)
+	{
+		push @problematic_lines, $_;
+	}
+}
+close $fh;
+
+if (@problematic_lines)
+{
+	print "libpq must not be calling any function which invokes exit\n";
+	print "Problematic symbol references:\n";
+	print @problematic_lines;
+
+	exit 1;
+}
+# Create stamp file, if required
+if (defined($stamp_file))
+{
+	create_stamp_file();
+}
+
+exit 0;
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index a74e885b169d..e71ee9058030 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -85,6 +85,25 @@ libpq = declare_dependency(
   include_directories: [include_directories('.')]
 )
 
+# Check for functions that libpq must not call.  See libpq-check.pl for the
+# full set of platform rules.  Skip the test when profiling, as gcc may
+# insert exit() calls for that.
+if nm.found() and not get_option('b_coverage')
+  custom_target(
+    'libpq-check',
+    input: libpq_so,
+    output: 'libpq-refs-stamp',
+    command: [
+      perl,
+        files('libpq-check.pl'),
+          '--input_file', '@INPUT@',
+          '--stamp_file', '@OUTPUT@',
+	  '--nm', nm.full_path()
+    ],
+    build_by_default: true,
+  )
+endif
+
 private_deps = [
   frontend_stlib_code,
   libpq_deps,
diff --git a/configure b/configure
index 3a0ed11fa8e2..ec35de5ba657 100755
--- a/configure
+++ b/configure
@@ -682,6 +682,7 @@ FLEXFLAGS
 FLEX
 BISONFLAGS
 BISON
+NM
 MKDIR_P
 LN_S
 TAR
@@ -10162,6 +10163,47 @@ case $MKDIR_P in
   *install-sh*) MKDIR_P='\${SHELL} \${top_srcdir}/config/install-sh -c -d';;
 esac
 
+# Extract the first word of "nm", so it can be a program name with args.
+set dummy nm; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_path_NM+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  case $NM in
+  [\\/]* | ?:[\\/]*)
+  ac_cv_path_NM="$NM" # Let the user override the test with a path.
+  ;;
+  *)
+  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+    ac_cv_path_NM="$as_dir/$ac_word$ac_exec_ext"
+    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+  ;;
+esac
+fi
+NM=$ac_cv_path_NM
+if test -n "$NM"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $NM" >&5
+$as_echo "$NM" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+
 if test -z "$BISON"; then
   for ac_prog in bison
 do
diff --git a/configure.ac b/configure.ac
index c2413720a188..7284f1ff6229 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1214,6 +1214,8 @@ case $MKDIR_P in
   *install-sh*) MKDIR_P='\${SHELL} \${top_srcdir}/config/install-sh -c -d';;
 esac
 
+AC_PATH_PROG(NM, nm)
+AC_SUBST(NM)
 PGAC_PATH_BISON
 PGAC_PATH_FLEX
 
diff --git a/meson.build b/meson.build
index 6e7ddd74683c..622598546ae8 100644
--- a/meson.build
+++ b/meson.build
@@ -350,6 +350,7 @@ missing = find_program('config/missing', native: true)
 cp = find_program('cp', required: false, native: true)
 xmllint_bin = find_program(get_option('XMLLINT'), native: true, required: false)
 xsltproc_bin = find_program(get_option('XSLTPROC'), native: true, required: false)
+nm = find_program('nm', required: false, native: true)
 
 bison_flags = []
 if bison.found()
diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 0aa389bc7101..371cd7eba2c1 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -292,6 +292,7 @@ FLEX = @FLEX@
 FLEXFLAGS = @FLEXFLAGS@ $(LFLAGS)
 DTRACE = @DTRACE@
 DTRACEFLAGS = @DTRACEFLAGS@
+NM = @NM@
 ZIC = @ZIC@
 
 # Linking
-- 
2.51.0

From e8bf515b01902b6fea05cb8bd87df18d001dac27 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Thu, 4 Dec 2025 09:13:49 +0900
Subject: [PATCH v5 2/2] libpq: Authorize pthread_exit() in libpq-check

---
 src/interfaces/libpq/libpq-check.pl | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/interfaces/libpq/libpq-check.pl b/src/interfaces/libpq/libpq-check.pl
index 274e873d1fca..1b610d9dc761 100755
--- a/src/interfaces/libpq/libpq-check.pl
+++ b/src/interfaces/libpq/libpq-check.pl
@@ -55,9 +55,11 @@ while (<$fh>)
 	# Set of symbols allowed:
 	#     __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
 	#     __tsan_func_exit - ThreadSanitizer instrumentation
+	#     pthread_exit     - legitimate thread cleanup
 
 	next if /__cxa_atexit/;
 	next if /__tsan_func_exit/;
+	next if /pthread_exit/;
 
 	# Anything containing "exit" is suspicious.
 	# (Ideally we should reject abort() too, but there are various scenarios
-- 
2.51.0

From 66aac3d1a3c1e51517b91175088bd99a0c20681c Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Thu, 4 Dec 2025 12:02:48 +0530
Subject: [PATCH v6 1/2] libpq: centralize exit() check logic and unify
 Makefile/Meson behavior

Move the libpq exit() reference check into a shared Perl script
(libpq-exit-check) and use it for both autoconf/Makefile and Meson
builds.  This avoids duplicated logic and ensures consistent
platform-specific handling of whitelisted symbols.

The script now receives the full path to `nm`, detected at the
top-level configure using AC_PATH_PROG and propagated via NM_PROG.
Both Makefile and Meson invoke the script with --nm=<path>.

Platform-specific behavior (Solaris skip, Windows skip, whitelisted
symbols, nm availability checks) is centralized inside the script.

This makes the two build systems apply the same exit() policy and keeps
all rules in one place.
---
 configure.ac                        |  2 +
 meson.build                         |  1 +
 src/Makefile.global.in              |  1 +
 src/interfaces/libpq/Makefile       | 21 ++------
 src/interfaces/libpq/libpq-check.pl | 83 +++++++++++++++++++++++++++++
 src/interfaces/libpq/meson.build    | 19 +++++++
 6 files changed, 110 insertions(+), 17 deletions(-)
 create mode 100644 src/interfaces/libpq/libpq-check.pl

diff --git a/configure.ac b/configure.ac
index c241372..7284f1f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1214,6 +1214,8 @@ case $MKDIR_P in
   *install-sh*) MKDIR_P='\${SHELL} \${top_srcdir}/config/install-sh -c -d';;
 esac
 
+AC_PATH_PROG(NM, nm)
+AC_SUBST(NM)
 PGAC_PATH_BISON
 PGAC_PATH_FLEX
 
diff --git a/meson.build b/meson.build
index 6e7ddd7..6225985 100644
--- a/meson.build
+++ b/meson.build
@@ -350,6 +350,7 @@ missing = find_program('config/missing', native: true)
 cp = find_program('cp', required: false, native: true)
 xmllint_bin = find_program(get_option('XMLLINT'), native: true, required: false)
 xsltproc_bin = find_program(get_option('XSLTPROC'), native: true, required: false)
+nm = find_program('nm', required: false, native: true)
 
 bison_flags = []
 if bison.found()
diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 0aa389b..371cd7e 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -292,6 +292,7 @@ FLEX = @FLEX@
 FLEXFLAGS = @FLEXFLAGS@ $(LFLAGS)
 DTRACE = @DTRACE@
 DTRACEFLAGS = @DTRACEFLAGS@
+NM = @NM@
 ZIC = @ZIC@
 
 # Linking
diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index da66500..1b7d3ec 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -129,25 +129,12 @@ $(shlib): $(OBJS_SHLIB)
 $(stlib): override OBJS += $(OBJS_STATIC)
 $(stlib): $(OBJS_STATIC)
 
-# Check for functions that libpq must not call, currently just exit().
-# (Ideally we'd reject abort() too, but there are various scenarios where
-# build toolchains insert abort() calls, e.g. to implement assert().)
-# If nm doesn't exist or doesn't work on shlibs, this test will do nothing,
-# which is fine.  The exclusion of __cxa_atexit is necessary on OpenBSD,
-# which seems to insert references to that even in pure C code. Excluding
-# __tsan_func_exit is necessary when using ThreadSanitizer data race detector
-# which use this function for instrumentation of function exit.
-# Skip the test when profiling, as gcc may insert exit() calls for that.
-# Also skip the test on platforms where libpq infrastructure may be provided
-# by statically-linked libraries, as we can't expect them to honor this
-# coding rule.
+# Check for functions that libpq must not call.  See libpq-check.pl for the
+# full set of platform rules.  Skip the test when profiling, as gcc may
+# insert exit() calls for that.
 libpq-refs-stamp: $(shlib)
 ifneq ($(enable_coverage), yes)
-ifeq (,$(filter solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v -e __cxa_atexit -e __tsan_func_exit | grep exit; then \
-		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
-	fi
-endif
+	$(PERL) libpq-check.pl --input_file $< --nm='$(NM)'
 endif
 	touch $@
 
diff --git a/src/interfaces/libpq/libpq-check.pl b/src/interfaces/libpq/libpq-check.pl
new file mode 100644
index 0000000..d4220ef
--- /dev/null
+++ b/src/interfaces/libpq/libpq-check.pl
@@ -0,0 +1,83 @@
+#!/usr/bin/perl
+#
+# src/interfaces/libpq/libpq-check.pl
+#
+# Copyright (c) 2025, PostgreSQL Global Development Group
+#
+# Check that the state of a libpq library.  Currently, this script checks
+# that exit() is not called, because client libraries must not terminate
+# the host application.
+#
+# This script is called by both Makefile and Meson.
+
+use strict;
+use warnings FATAL => 'all';
+
+use Getopt::Long;
+use Config;
+
+my $nm_path;
+my $input_file;
+my $stamp_file;
+my @problematic_lines;
+
+Getopt::Long::GetOptions(
+    'nm:s'         => \$nm_path,
+    'input_file:s' => \$input_file,
+    'stamp_file:s' => \$stamp_file
+) or die "$0: wrong arguments\n";
+
+die "$0: --input_file must be specified\n" unless defined $input_file;
+die "$0: --nm must be specified\n" unless defined $nm_path and -x $nm_path;
+
+sub create_stamp_file {
+    if ( !( -f $stamp_file ) ) {
+        open my $fh, '>', $stamp_file
+          or die "can't open $stamp_file: $!";
+        close $fh;
+    }
+}
+
+# ---- Skip on Windows and Solaris ----
+if (   $Config{osname} =~ /MSWin32|cygwin|msys/i
+    || $Config{osname} =~ /solaris/i )
+{
+    exit 0;
+}
+
+# Run nm to scan for symbols.  If nm fails at runtime, skip the check.
+open my $fh, '-|', "$nm_path -A -u $input_file 2>/dev/null"
+  or exit 0;
+
+while (<$fh>) {
+
+    # Set of symbols allowed:
+    #     __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
+    #     __tsan_func_exit - ThreadSanitizer instrumentation
+
+    next if /__cxa_atexit/;
+    next if /__tsan_func_exit/;
+
+    # Anything containing "exit" is suspicious.
+    # (Ideally we should reject abort() too, but there are various scenarios
+    # where build toolchains insert abort() calls, e.g. to implement assert().)
+    if (/exit/) {
+        push @problematic_lines, $_;
+    }
+}
+close $fh;
+
+if (@problematic_lines) {
+    print "libpq must not be calling any function which invokes exit\n";
+    print "Problematic symbol references:\n";
+    print @problematic_lines;
+
+    exit 1;
+}
+
+# Create stamp file, if required
+if ( defined($stamp_file) ) {
+    create_stamp_file();
+}
+
+exit 0;
diff --git a/src/interfaces/libpq/meson.build b/src/interfaces/libpq/meson.build
index a74e885..52da79c 100644
--- a/src/interfaces/libpq/meson.build
+++ b/src/interfaces/libpq/meson.build
@@ -85,6 +85,25 @@ libpq = declare_dependency(
   include_directories: [include_directories('.')]
 )
 
+# Check for functions that libpq must not call.  See libpq-check.pl for the
+# full set of platform rules.  Skip the test when profiling, as gcc may
+# insert exit() calls for that.
+if nm.found() and not get_option('b_coverage')
+  custom_target(
+    'libpq-check',
+    input: libpq_so,
+    output: 'libpq-refs-stamp',
+    command: [
+      perl,
+        files('libpq-check.pl'),
+          '--input_file', '@INPUT@',
+          '--stamp_file', '@OUTPUT@',
+          '--nm', nm.full_path()
+    ],
+    build_by_default: true,
+  )
+endif
+
 private_deps = [
   frontend_stlib_code,
   libpq_deps,
-- 
2.43.0

From ae11ebe777cd228fb3ddf69cc05cbc816301c41f Mon Sep 17 00:00:00 2001
From: BharatDBPG <bharatdbpg@gmail.com>
Date: Thu, 4 Dec 2025 12:08:07 +0530
Subject: [PATCH v6 2/2] libpq: whitelisting pthread_exit() in libpq-check.

---
 src/interfaces/libpq/libpq-check.pl | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/interfaces/libpq/libpq-check.pl b/src/interfaces/libpq/libpq-check.pl
index d4220ef..13e977d 100644
--- a/src/interfaces/libpq/libpq-check.pl
+++ b/src/interfaces/libpq/libpq-check.pl
@@ -54,9 +54,11 @@ while (<$fh>) {
     # Set of symbols allowed:
     #     __cxa_atexit     - injected by some libcs (e.g., OpenBSD)
     #     __tsan_func_exit - ThreadSanitizer instrumentation
+    #     pthread_exit     - legitimate thread cleanup
 
     next if /__cxa_atexit/;
     next if /__tsan_func_exit/;
+    next if /pthread_exit/;
 
     # Anything containing "exit" is suspicious.
     # (Ideally we should reject abort() too, but there are various scenarios
-- 
2.43.0

diff --git a/src/makefiles/meson.build b/src/makefiles/meson.build
index 0def244c9011..c6edf14ec449 100644
--- a/src/makefiles/meson.build
+++ b/src/makefiles/meson.build
@@ -154,9 +154,10 @@ pgxs_bins = {
 pgxs_empty = [
   'ICU_CFLAGS', # needs to be added, included by public server headers
 
-  # hard to see why we'd need either?
+  # hard to see why we'd need these ones?
   'ZIC',
   'TCLSH',
+  'NM',
 
   # docs don't seem to be supported by pgxs
   'XMLLINT',