From c03073774f915fe7841c2b551fe304544143470f Mon Sep 17 00:00:00 2001 From: Zack Weinberg Date: Tue, 6 Dec 2016 10:14:42 -0500 Subject: Make _REENTRANT and _THREAD_SAFE aliases for _POSIX_C_SOURCE=199506L. For many years, the only effect of these macros has been to make unistd.h declare getlogin_r. _POSIX_C_SOURCE >= 199506L also causes this function to be declared. However, people who don't carefully read all the headers might be confused into thinking they need to define _REENTRANT for any threaded code (as was indeed the case a long time ago). Therefore, remove __USE_REENTRANT, and make _REENTRANT and _THREAD_SAFE into synonyms for _POSIX_C_SOURCE=199506L. This will only affect programs that don't select a higher conformance level some other way. For instance, -std=c89 -D_REENTRANT will see a change in visible declarations, but -std=c99 -D_POSIX_C_SOURCE=200809L -D_REENTRANT won't, and -D_REENTRANT all by itself also won't, because _DEFAULT_SOURCE implies _POSIX_C_SOURCE > 199506. * include/features.h: Remove __USE_REENTRANT. Treat _REENTRANT and _THREAD_SAFE the same as _POSIX_C_SOURCE=199506L, if a higher POSIX conformance level has not been selected by other macros. * NEWS, manual/creature.texi: Document this change. * posix/unistd.h, posix/bits/unistd.h: Don't check __USE_REENTRANT. * include/libc-symbols.h: Don't define _REENTRANT. * scripts/check-installed-headers.sh: Don't undefine _REENTRANT. --- scripts/check-installed-headers.sh | 1 - 1 file changed, 1 deletion(-) (limited to 'scripts') diff --git a/scripts/check-installed-headers.sh b/scripts/check-installed-headers.sh index a245fe6be2..89e1514c7b 100644 --- a/scripts/check-installed-headers.sh +++ b/scripts/check-installed-headers.sh @@ -143,7 +143,6 @@ EOF inappropriate for this test. */ #undef _LIBC #undef _GNU_SOURCE -#undef _REENTRANT /* The library mode is selected here rather than on the command line to ensure that this selection wins. */ $expanded_lib_mode -- cgit 1.4.1