diff options
author | Tom Lane | 2018-09-30 20:24:56 +0000 |
---|---|---|
committer | Tom Lane | 2018-09-30 20:24:56 +0000 |
commit | 08aad3c81effab6307b436de54f5ccbe7a9b9a6e (patch) | |
tree | e27dd2a05ef11d7204c2fdde36f83893f69ec942 | |
parent | 14ce78e478b1708bc146685ea1870cc18d6181a4 (diff) |
Fix detection of the result type of strerror_r().
The method we've traditionally used, of redeclaring strerror_r() to
see if the compiler complains of inconsistent declarations, turns out
not to work reliably because some compilers only report a warning,
not an error. Amazingly, this has gone undetected for years, even
though it certainly breaks our detection of whether strerror_r
succeeded.
Let's instead test whether the compiler will take the result of
strerror_r() as a switch() argument. It's possible this won't
work universally either, but it's the best idea I could come up with
on the spur of the moment.
Back-patch of commit 751f532b9. Buildfarm results indicate that only
icc-on-Linux actually has an issue here; perhaps the lack of field
reports indicates that people don't build PG for production that way.
Discussion: https://postgr.es/m/[email protected]
-rw-r--r-- | config/c-library.m4 | 19 | ||||
-rwxr-xr-x | configure | 12 | ||||
-rw-r--r-- | src/include/pg_config.h.in | 2 | ||||
-rw-r--r-- | src/include/pg_config.h.win32 | 2 |
4 files changed, 17 insertions, 18 deletions
diff --git a/config/c-library.m4 b/config/c-library.m4 index 70eb0e4dcf..949f3a5e34 100644 --- a/config/c-library.m4 +++ b/config/c-library.m4 @@ -102,22 +102,23 @@ fi # PGAC_FUNC_STRERROR_R_INT # --------------------------- -# Check if strerror_r() returns an int (SUSv3) rather than a char * (GNU libc) -# If so, define STRERROR_R_INT +# Check if strerror_r() returns int (POSIX) rather than char * (GNU libc). +# If so, define STRERROR_R_INT. +# The result is uncertain if strerror_r() isn't provided, +# but we don't much care. AC_DEFUN([PGAC_FUNC_STRERROR_R_INT], [AC_CACHE_CHECK(whether strerror_r returns int, pgac_cv_func_strerror_r_int, [AC_TRY_COMPILE([#include <string.h>], -[#ifndef _AIX -int strerror_r(int, char *, size_t); -#else -/* Older AIX has 'int' for the third argument so we don't test the args. */ -int strerror_r(); -#endif], +[char buf[100]; + switch (strerror_r(1, buf, sizeof(buf))) + { case 0: break; default: break; } +], [pgac_cv_func_strerror_r_int=yes], [pgac_cv_func_strerror_r_int=no])]) if test x"$pgac_cv_func_strerror_r_int" = xyes ; then - AC_DEFINE(STRERROR_R_INT,, [Define to 1 if strerror_r() returns a int.]) + AC_DEFINE(STRERROR_R_INT, 1, + [Define to 1 if strerror_r() returns int.]) fi ])# PGAC_FUNC_STRERROR_R_INT @@ -24978,12 +24978,10 @@ cat >>conftest.$ac_ext <<_ACEOF int main () { -#ifndef _AIX -int strerror_r(int, char *, size_t); -#else -/* Older AIX has 'int' for the third argument so we don't test the args. */ -int strerror_r(); -#endif +char buf[100]; + switch (strerror_r(1, buf, sizeof(buf))) + { case 0: break; default: break; } + ; return 0; } @@ -25021,7 +25019,7 @@ $as_echo "$pgac_cv_func_strerror_r_int" >&6; } if test x"$pgac_cv_func_strerror_r_int" = xyes ; then cat >>confdefs.h <<\_ACEOF -#define STRERROR_R_INT /**/ +#define STRERROR_R_INT 1 _ACEOF fi diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in index 0121ea8028..3c553b4560 100644 --- a/src/include/pg_config.h.in +++ b/src/include/pg_config.h.in @@ -773,7 +773,7 @@ /* Define to 1 if you have the ANSI C header files. */ #undef STDC_HEADERS -/* Define to 1 if strerror_r() returns a int. */ +/* Define to 1 if strerror_r() returns int. */ #undef STRERROR_R_INT /* Define to 1 if your <sys/time.h> declares `struct tm'. */ diff --git a/src/include/pg_config.h.win32 b/src/include/pg_config.h.win32 index c287da3212..140912d71b 100644 --- a/src/include/pg_config.h.win32 +++ b/src/include/pg_config.h.win32 @@ -633,7 +633,7 @@ /* Define to 1 if you have the ANSI C header files. */ #define STDC_HEADERS 1 -/* Define to 1 if strerror_r() returns a int. */ +/* Define to 1 if strerror_r() returns int. */ /* #undef STRERROR_R_INT */ /* Define to 1 if your <sys/time.h> declares `struct tm'. */ |