From 5fbc7dc89d309f7094a81e77703ec0b5339be7f7 Mon Sep 17 00:00:00 2001 From: Jelte Fennema-Nio Date: Sat, 3 Jan 2026 00:43:59 +0100 Subject: [PATCH v5 3/4] Revert "Replace pg_restrict by standard restrict" This reverts commit f0f2c0c1aef95757c4e7f144d5577e2b0d814279. It turns out that this completely broke compiling C++ extensions on MSVC. The restrict replacement with __restrict would break usages of __decltype(restrict) in standard library headers, resulting in errors like this: C:\Program Files (x86)\Windows Kits\10\include\10.0.22621.0\ucrt\corecrt_malloc.h(58): error C2485: '__restrict': unrecognized extended attribute --- configure | 18 ++++++++++++++---- configure.ac | 16 ++++++++++++---- meson.build | 13 +++++++------ src/bin/pg_verifybackup/pg_verifybackup.c | 4 ++-- src/bin/pg_verifybackup/pg_verifybackup.h | 4 ++-- src/common/logging.c | 4 ++-- src/common/string.c | 2 +- src/include/c.h | 6 ------ src/include/common/logging.h | 4 ++-- src/include/common/string.h | 2 +- src/include/libpq/pqformat.h | 12 ++++++------ src/include/pg_config.h.in | 4 ++++ 12 files changed, 53 insertions(+), 36 deletions(-) diff --git a/configure b/configure index 045c913865d..575f4f05245 100755 --- a/configure +++ b/configure @@ -15131,10 +15131,10 @@ _ACEOF fi -# Even though restrict is in C99 and should be supported by all -# supported compilers, this test is useful because it will prefer a -# spelling that also works in C++ (often __restrict). (restrict is -# not part of the C++ standard.) +# MSVC doesn't cope well with defining restrict to __restrict, the +# spelling it understands, because it conflicts with +# __declspec(restrict). Therefore we define pg_restrict to the +# appropriate definition, which presumably won't conflict. { $as_echo "$as_me:${as_lineno-$LINENO}: checking for C/C++ restrict keyword" >&5 $as_echo_n "checking for C/C++ restrict keyword... " >&6; } if ${ac_cv_c_restrict+:} false; then : @@ -15181,6 +15181,16 @@ _ACEOF ;; esac +if test "$ac_cv_c_restrict" = "no"; then + pg_restrict="" +else + pg_restrict="$ac_cv_c_restrict" +fi + +cat >>confdefs.h <<_ACEOF +#define pg_restrict $pg_restrict +_ACEOF + ac_fn_c_check_type "$LINENO" "struct option" "ac_cv_type_struct_option" "#ifdef HAVE_GETOPT_H #include diff --git a/configure.ac b/configure.ac index 145197e6bd6..c77c2639ec1 100644 --- a/configure.ac +++ b/configure.ac @@ -1687,11 +1687,19 @@ PGAC_UNION_SEMUN AC_CHECK_TYPES(socklen_t, [], [], [#include ]) PGAC_STRUCT_SOCKADDR_SA_LEN -# Even though restrict is in C99 and should be supported by all -# supported compilers, this test is useful because it will prefer a -# spelling that also works in C++ (often __restrict). (restrict is -# not part of the C++ standard.) +# MSVC doesn't cope well with defining restrict to __restrict, the +# spelling it understands, because it conflicts with +# __declspec(restrict). Therefore we define pg_restrict to the +# appropriate definition, which presumably won't conflict. AC_C_RESTRICT +if test "$ac_cv_c_restrict" = "no"; then + pg_restrict="" +else + pg_restrict="$ac_cv_c_restrict" +fi +AC_DEFINE_UNQUOTED([pg_restrict], [$pg_restrict], +[Define to keyword to use for C99 restrict support, or to nothing if not +supported]) AC_CHECK_TYPES([struct option], [], [], [#ifdef HAVE_GETOPT_H diff --git a/meson.build b/meson.build index 555c94796c6..55df1dd3797 100644 --- a/meson.build +++ b/meson.build @@ -2833,12 +2833,13 @@ int main(void) endforeach -# Even though restrict is in C99 and should be supported by all -# supported compilers, this indirection is useful because __restrict -# also works in C++ in all supported compilers. (If not, then we -# might have to write a real test.) (restrict is not part of the C++ -# standard.) -cdata.set('restrict', '__restrict') +# MSVC doesn't cope well with defining restrict to __restrict, the spelling it +# understands, because it conflicts with __declspec(restrict). Therefore we +# define pg_restrict to the appropriate definition, which presumably won't +# conflict. +# +# We assume C99 support, so we don't need to make this conditional. +cdata.set('pg_restrict', '__restrict') # Most libraries are included only if they demonstrably provide a function we diff --git a/src/bin/pg_verifybackup/pg_verifybackup.c b/src/bin/pg_verifybackup/pg_verifybackup.c index 456e0375e13..f9f2d457f2f 100644 --- a/src/bin/pg_verifybackup/pg_verifybackup.c +++ b/src/bin/pg_verifybackup/pg_verifybackup.c @@ -1228,7 +1228,7 @@ parse_required_wal(verifier_context *context, char *pg_waldump_path, * context says we should. */ void -report_backup_error(verifier_context *context, const char *restrict fmt,...) +report_backup_error(verifier_context *context, const char *pg_restrict fmt,...) { va_list ap; @@ -1245,7 +1245,7 @@ report_backup_error(verifier_context *context, const char *restrict fmt,...) * Report a fatal error and exit */ void -report_fatal_error(const char *restrict fmt,...) +report_fatal_error(const char *pg_restrict fmt,...) { va_list ap; diff --git a/src/bin/pg_verifybackup/pg_verifybackup.h b/src/bin/pg_verifybackup/pg_verifybackup.h index 1cd76a8826b..a99d9bfd581 100644 --- a/src/bin/pg_verifybackup/pg_verifybackup.h +++ b/src/bin/pg_verifybackup/pg_verifybackup.h @@ -96,9 +96,9 @@ typedef struct verifier_context } verifier_context; extern void report_backup_error(verifier_context *context, - const char *restrict fmt,...) + const char *pg_restrict fmt,...) pg_attribute_printf(2, 3); -pg_noreturn extern void report_fatal_error(const char *restrict fmt,...) +pg_noreturn extern void report_fatal_error(const char *pg_restrict fmt,...) pg_attribute_printf(1, 2); extern bool should_ignore_relpath(verifier_context *context, const char *relpath); diff --git a/src/common/logging.c b/src/common/logging.c index 214a87f2189..5206949e5d8 100644 --- a/src/common/logging.c +++ b/src/common/logging.c @@ -206,7 +206,7 @@ pg_logging_set_locus_callback(void (*cb) (const char **filename, uint64 *lineno) void pg_log_generic(enum pg_log_level level, enum pg_log_part part, - const char *restrict fmt,...) + const char *pg_restrict fmt,...) { va_list ap; @@ -217,7 +217,7 @@ pg_log_generic(enum pg_log_level level, enum pg_log_part part, void pg_log_generic_v(enum pg_log_level level, enum pg_log_part part, - const char *restrict fmt, va_list ap) + const char *pg_restrict fmt, va_list ap) { int save_errno = errno; const char *filename = NULL; diff --git a/src/common/string.c b/src/common/string.c index fff14d3facf..41c74a1502d 100644 --- a/src/common/string.c +++ b/src/common/string.c @@ -47,7 +47,7 @@ pg_str_endswith(const char *str, const char *end) * strtoint --- just like strtol, but returns int not long */ int -strtoint(const char *restrict str, char **restrict endptr, int base) +strtoint(const char *pg_restrict str, char **pg_restrict endptr, int base) { long val; diff --git a/src/include/c.h b/src/include/c.h index 39105671e6c..65173b9d9fd 100644 --- a/src/include/c.h +++ b/src/include/c.h @@ -108,12 +108,6 @@ #define inline #endif -/* - * Previously used PostgreSQL-specific spelling, for backward compatibility - * for extensions. - */ -#define pg_restrict restrict - /* * Attribute macros * diff --git a/src/include/common/logging.h b/src/include/common/logging.h index b5caec0bff1..bccba4ac07b 100644 --- a/src/include/common/logging.h +++ b/src/include/common/logging.h @@ -93,10 +93,10 @@ void pg_logging_set_pre_callback(void (*cb) (void)); void pg_logging_set_locus_callback(void (*cb) (const char **filename, uint64 *lineno)); void pg_log_generic(enum pg_log_level level, enum pg_log_part part, - const char *restrict fmt,...) + const char *pg_restrict fmt,...) pg_attribute_printf(3, 4); void pg_log_generic_v(enum pg_log_level level, enum pg_log_part part, - const char *restrict fmt, va_list ap) + const char *pg_restrict fmt, va_list ap) pg_attribute_printf(3, 0); /* diff --git a/src/include/common/string.h b/src/include/common/string.h index 5e1bd61c710..2a7c31ea74e 100644 --- a/src/include/common/string.h +++ b/src/include/common/string.h @@ -25,7 +25,7 @@ typedef struct PromptInterruptContext /* functions in src/common/string.c */ extern bool pg_str_endswith(const char *str, const char *end); -extern int strtoint(const char *restrict str, char **restrict endptr, +extern int strtoint(const char *pg_restrict str, char **pg_restrict endptr, int base); extern char *pg_clean_ascii(const char *str, int alloc_flags); extern int pg_strip_crlf(char *str); diff --git a/src/include/libpq/pqformat.h b/src/include/libpq/pqformat.h index 911d9397f5e..bc4ab1381a9 100644 --- a/src/include/libpq/pqformat.h +++ b/src/include/libpq/pqformat.h @@ -34,7 +34,7 @@ extern void pq_sendfloat8(StringInfo buf, float8 f); * Append a [u]int8 to a StringInfo buffer, which already has enough space * preallocated. * - * The use of restrict allows the compiler to optimize the code based on + * The use of pg_restrict allows the compiler to optimize the code based on * the assumption that buf, buf->len, buf->data and *buf->data don't * overlap. Without the annotation buf->len etc cannot be kept in a register * over subsequent pq_writeintN calls. @@ -43,7 +43,7 @@ extern void pq_sendfloat8(StringInfo buf, float8 f); * overly picky and demanding a * before a restrict. */ static inline void -pq_writeint8(StringInfoData *restrict buf, uint8 i) +pq_writeint8(StringInfoData *pg_restrict buf, uint8 i) { uint8 ni = i; @@ -57,7 +57,7 @@ pq_writeint8(StringInfoData *restrict buf, uint8 i) * preallocated. */ static inline void -pq_writeint16(StringInfoData *restrict buf, uint16 i) +pq_writeint16(StringInfoData *pg_restrict buf, uint16 i) { uint16 ni = pg_hton16(i); @@ -71,7 +71,7 @@ pq_writeint16(StringInfoData *restrict buf, uint16 i) * preallocated. */ static inline void -pq_writeint32(StringInfoData *restrict buf, uint32 i) +pq_writeint32(StringInfoData *pg_restrict buf, uint32 i) { uint32 ni = pg_hton32(i); @@ -85,7 +85,7 @@ pq_writeint32(StringInfoData *restrict buf, uint32 i) * preallocated. */ static inline void -pq_writeint64(StringInfoData *restrict buf, uint64 i) +pq_writeint64(StringInfoData *pg_restrict buf, uint64 i) { uint64 ni = pg_hton64(i); @@ -105,7 +105,7 @@ pq_writeint64(StringInfoData *restrict buf, uint64 i) * sent to the frontend. */ static inline void -pq_writestring(StringInfoData *restrict buf, const char *restrict str) +pq_writestring(StringInfoData *pg_restrict buf, const char *pg_restrict str) { int slen = strlen(str); char *p; diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in index 10fa85e78c2..339268dc8ef 100644 --- a/src/include/pg_config.h.in +++ b/src/include/pg_config.h.in @@ -786,6 +786,10 @@ #undef inline #endif +/* Define to keyword to use for C99 restrict support, or to nothing if not + supported */ +#undef pg_restrict + /* Define to the equivalent of the C99 'restrict' keyword, or to nothing if this is not supported. Do not define if restrict is supported directly. */ -- 2.52.0