From fb38dffa1b0e166a3045b751794f939bc1f01f0f Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Mon, 18 Nov 2024 12:09:09 +1300 Subject: [PATCH 1/2] Assume that exists. Previously we checked "for that conforms to C99" using autoconf's AC_CHECK_HEADER_STDBOOL macro. Since we require C99, it must always exist these days, but the macro as defined doesn't cope with C23's empty header. Later autoconf versions fixed that, but let's just remove the anachronistic test. HAVE_STDBOOL_H and HAVE__BOOL will no longer be defined, but they weren't directly tested in core, or likely extensions. PG_USE_STDBOOL is still defined when sizeof(bool) is 1: in practice always. Otherwise, we define our own bool type and values, also certain to fail on C23 as coded, but we don't know of any system like that in modern times. Further cleanup work is possible, but that'd be master-only. This came to our attention when GCC 15 recently flipped the C23 switch by default. Back-patch to all supported releases. Reported-by: Sam James Reviewed-by: Discussion: https://www.postgresql.org/message-id/flat/87o72eo9iu.fsf%40gentoo.org --- configure | 182 +++++++++---------------------------- configure.ac | 13 +-- meson.build | 9 +- src/include/c.h | 2 +- src/include/pg_config.h.in | 6 -- 5 files changed, 51 insertions(+), 161 deletions(-) diff --git a/configure b/configure index f58eae1baa8..001f0e5d46a 100755 --- a/configure +++ b/configure @@ -2094,116 +2094,116 @@ $as_echo "$ac_res" >&6; } } # ac_fn_c_check_func -# ac_fn_c_check_type LINENO TYPE VAR INCLUDES -# ------------------------------------------- -# Tests whether TYPE exists after having included INCLUDES, setting cache -# variable VAR accordingly. -ac_fn_c_check_type () +# ac_fn_c_check_member LINENO AGGR MEMBER VAR INCLUDES +# ---------------------------------------------------- +# Tries to find if the field MEMBER exists in type AGGR, after including +# INCLUDES, setting cache variable VAR accordingly. +ac_fn_c_check_member () { as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack - { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5 -$as_echo_n "checking for $2... " >&6; } -if eval \${$3+:} false; then : + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2.$3" >&5 +$as_echo_n "checking for $2.$3... " >&6; } +if eval \${$4+:} false; then : $as_echo_n "(cached) " >&6 else - eval "$3=no" cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ -$4 +$5 int main () { -if (sizeof ($2)) - return 0; +static $2 ac_aggr; +if (ac_aggr.$3) +return 0; ; return 0; } _ACEOF if ac_fn_c_try_compile "$LINENO"; then : + eval "$4=yes" +else cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ -$4 +$5 int main () { -if (sizeof (($2))) - return 0; +static $2 ac_aggr; +if (sizeof ac_aggr.$3) +return 0; ; return 0; } _ACEOF if ac_fn_c_try_compile "$LINENO"; then : - + eval "$4=yes" else - eval "$3=yes" + eval "$4=no" fi rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext fi rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext fi -eval ac_res=\$$3 +eval ac_res=\$$4 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5 $as_echo "$ac_res" >&6; } eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno -} # ac_fn_c_check_type +} # ac_fn_c_check_member -# ac_fn_c_check_member LINENO AGGR MEMBER VAR INCLUDES -# ---------------------------------------------------- -# Tries to find if the field MEMBER exists in type AGGR, after including -# INCLUDES, setting cache variable VAR accordingly. -ac_fn_c_check_member () +# ac_fn_c_check_type LINENO TYPE VAR INCLUDES +# ------------------------------------------- +# Tests whether TYPE exists after having included INCLUDES, setting cache +# variable VAR accordingly. +ac_fn_c_check_type () { as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack - { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2.$3" >&5 -$as_echo_n "checking for $2.$3... " >&6; } -if eval \${$4+:} false; then : + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5 +$as_echo_n "checking for $2... " >&6; } +if eval \${$3+:} false; then : $as_echo_n "(cached) " >&6 else + eval "$3=no" cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ -$5 +$4 int main () { -static $2 ac_aggr; -if (ac_aggr.$3) -return 0; +if (sizeof ($2)) + return 0; ; return 0; } _ACEOF if ac_fn_c_try_compile "$LINENO"; then : - eval "$4=yes" -else cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ -$5 +$4 int main () { -static $2 ac_aggr; -if (sizeof ac_aggr.$3) -return 0; +if (sizeof (($2))) + return 0; ; return 0; } _ACEOF if ac_fn_c_try_compile "$LINENO"; then : - eval "$4=yes" + else - eval "$4=no" + eval "$3=yes" fi rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext fi rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext fi -eval ac_res=\$$4 +eval ac_res=\$$3 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5 $as_echo "$ac_res" >&6; } eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno -} # ac_fn_c_check_member +} # ac_fn_c_check_type # ac_fn_c_compute_int LINENO EXPR VAR INCLUDES # -------------------------------------------- @@ -13122,100 +13122,6 @@ fi ## Header files ## -{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for stdbool.h that conforms to C99" >&5 -$as_echo_n "checking for stdbool.h that conforms to C99... " >&6; } -if ${ac_cv_header_stdbool_h+:} false; then : - $as_echo_n "(cached) " >&6 -else - cat confdefs.h - <<_ACEOF >conftest.$ac_ext -/* end confdefs.h. */ - - #include - #ifndef bool - "error: bool is not defined" - #endif - #ifndef false - "error: false is not defined" - #endif - #if false - "error: false is not 0" - #endif - #ifndef true - "error: true is not defined" - #endif - #if true != 1 - "error: true is not 1" - #endif - #ifndef __bool_true_false_are_defined - "error: __bool_true_false_are_defined is not defined" - #endif - - struct s { _Bool s: 1; _Bool t; } s; - - char a[true == 1 ? 1 : -1]; - char b[false == 0 ? 1 : -1]; - char c[__bool_true_false_are_defined == 1 ? 1 : -1]; - char d[(bool) 0.5 == true ? 1 : -1]; - /* See body of main program for 'e'. */ - char f[(_Bool) 0.0 == false ? 1 : -1]; - char g[true]; - char h[sizeof (_Bool)]; - char i[sizeof s.t]; - enum { j = false, k = true, l = false * true, m = true * 256 }; - /* The following fails for - HP aC++/ANSI C B3910B A.05.55 [Dec 04 2003]. */ - _Bool n[m]; - char o[sizeof n == m * sizeof n[0] ? 1 : -1]; - char p[-1 - (_Bool) 0 < 0 && -1 - (bool) 0 < 0 ? 1 : -1]; - /* Catch a bug in an HP-UX C compiler. See - http://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html - http://lists.gnu.org/archive/html/bug-coreutils/2005-11/msg00161.html - */ - _Bool q = true; - _Bool *pq = &q; - -int -main () -{ - - bool e = &s; - *pq |= q; - *pq |= ! q; - /* Refer to every declared value, to avoid compiler optimizations. */ - return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !!j + !k + !!l - + !m + !n + !o + !p + !q + !pq); - - ; - return 0; -} -_ACEOF -if ac_fn_c_try_compile "$LINENO"; then : - ac_cv_header_stdbool_h=yes -else - ac_cv_header_stdbool_h=no -fi -rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext -fi -{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdbool_h" >&5 -$as_echo "$ac_cv_header_stdbool_h" >&6; } - ac_fn_c_check_type "$LINENO" "_Bool" "ac_cv_type__Bool" "$ac_includes_default" -if test "x$ac_cv_type__Bool" = xyes; then : - -cat >>confdefs.h <<_ACEOF -#define HAVE__BOOL 1 -_ACEOF - - -fi - - -if test $ac_cv_header_stdbool_h = yes; then - -$as_echo "#define HAVE_STDBOOL_H 1" >>confdefs.h - -fi - - for ac_header in atomic.h copyfile.h execinfo.h getopt.h ifaddrs.h mbarrier.h sys/epoll.h sys/event.h sys/personality.h sys/prctl.h sys/procctl.h sys/signalfd.h sys/ucred.h termios.h ucred.h xlocale.h do : as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh` @@ -14956,9 +14862,7 @@ $as_echo_n "checking size of bool... " >&6; } if ${ac_cv_sizeof_bool+:} false; then : $as_echo_n "(cached) " >&6 else - if ac_fn_c_compute_int "$LINENO" "(long int) (sizeof (bool))" "ac_cv_sizeof_bool" "#ifdef HAVE_STDBOOL_H -#include -#endif + if ac_fn_c_compute_int "$LINENO" "(long int) (sizeof (bool))" "ac_cv_sizeof_bool" "#include "; then : else @@ -14984,7 +14888,7 @@ _ACEOF -if test "$ac_cv_header_stdbool_h" = yes -a "$ac_cv_sizeof_bool" = 1; then +if test "$ac_cv_sizeof_bool" = 1; then $as_echo "#define PG_USE_STDBOOL 1" >>confdefs.h diff --git a/configure.ac b/configure.ac index 82c5009e3e8..f55579e5b55 100644 --- a/configure.ac +++ b/configure.ac @@ -1425,8 +1425,6 @@ AC_SUBST(UUID_LIBS) ## Header files ## -AC_HEADER_STDBOOL - AC_CHECK_HEADERS(m4_normalize([ atomic.h copyfile.h @@ -1686,14 +1684,11 @@ if test "$ac_cv_sizeof_off_t" -lt 8; then fi fi -AC_CHECK_SIZEOF([bool], [], -[#ifdef HAVE_STDBOOL_H -#include -#endif]) +AC_CHECK_SIZEOF([bool], [], [#include ]) -dnl We use if we have it and it declares type bool as having -dnl size 1. Otherwise, c.h will fall back to declaring bool as unsigned char. -if test "$ac_cv_header_stdbool_h" = yes -a "$ac_cv_sizeof_bool" = 1; then +dnl We use if bool has size 1 after including it. Otherwise, c.h +dnl will fall back to declaring bool as unsigned char. +if test "$ac_cv_sizeof_bool" = 1; then AC_DEFINE([PG_USE_STDBOOL], 1, [Define to 1 to use to define type bool.]) fi diff --git a/meson.build b/meson.build index 5b0510cef78..4aef6dde69b 100644 --- a/meson.build +++ b/meson.build @@ -1755,12 +1755,9 @@ if cc.compiles(''' endif -# We use if we have it and it declares type bool as having -# size 1. Otherwise, c.h will fall back to declaring bool as unsigned char. -if cc.has_type('_Bool', args: test_c_args) \ - and cc.has_type('bool', prefix: '#include ', args: test_c_args) \ - and cc.sizeof('bool', prefix: '#include ', args: test_c_args) == 1 - cdata.set('HAVE__BOOL', 1) +# We use bool has size 1 after including it. Otherwise, c.h will +# fall back to declaring bool as unsigned char. +if cc.sizeof('bool', prefix: '#include ', args: test_c_args) == 1 cdata.set('PG_USE_STDBOOL', 1) endif diff --git a/src/include/c.h b/src/include/c.h index 0a548d69d7f..b7352ed270c 100644 --- a/src/include/c.h +++ b/src/include/c.h @@ -450,7 +450,7 @@ typedef void (*pg_funcptr_t) (void); * bool * Boolean value, either true or false. * - * We use stdbool.h if available and its bool has size 1. That's useful for + * We use stdbool.h if bool has size 1 after including it. That's useful for * better compiler and debugger output and for compatibility with third-party * libraries. But PostgreSQL currently cannot deal with bool of other sizes; * there are static assertions around the code to prevent that. diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in index cdd9a6e9355..5220e1222f5 100644 --- a/src/include/pg_config.h.in +++ b/src/include/pg_config.h.in @@ -361,9 +361,6 @@ /* Define to 1 if you have the `SSL_CTX_set_num_tickets' function. */ #undef HAVE_SSL_CTX_SET_NUM_TICKETS -/* Define to 1 if stdbool.h conforms to C99. */ -#undef HAVE_STDBOOL_H - /* Define to 1 if you have the header file. */ #undef HAVE_STDINT_H @@ -493,9 +490,6 @@ /* Define to 1 if you have XSAVE intrinsics. */ #undef HAVE_XSAVE_INTRINSICS -/* Define to 1 if the system has the type `_Bool'. */ -#undef HAVE__BOOL - /* Define to 1 if your compiler understands __builtin_bswap16. */ #undef HAVE__BUILTIN_BSWAP16 -- 2.47.0