Re: GCC 11.1 Release Candidate available from gcc.gnu.org

[Jakub Jelinek <jakub@redhat.com>]

On Tue, Apr 20, 2021 at 10:12:33PM -0700, Thomas Rodgers wrote:
> I think the attached patch (also in BZ) addresses the issue in
> bits/semaphore_base.h, but I'm going to defer to Jonathan on why the macro
> name is being transformed incorrectly in the first place.

Jonathan's call, but for me it looks much better to fix up the
macro name on the configure side.
The include/Makefile.am sed is:
        sed -e 's/HAVE_/_GLIBCXX_HAVE_/g' \
            -e 's/PACKAGE/_GLIBCXX_PACKAGE/g' \
            -e 's/VERSION/_GLIBCXX_VERSION/g' \
            -e 's/WORDS_/_GLIBCXX_WORDS_/g' \
            -e 's/_DARWIN_USE_64_BIT_INODE/_GLIBCXX_DARWIN_USE_64_BIT_INODE/g' \
            -e 's/_FILE_OFFSET_BITS/_GLIBCXX_FILE_OFFSET_BITS/g' \
            -e 's/_LARGE_FILES/_GLIBCXX_LARGE_FILES/g' \
            -e 's/ICONV_CONST/_GLIBCXX_ICONV_CONST/g' \
            -e '/[       ]_GLIBCXX_LONG_DOUBLE_COMPAT[   ]/d' \
            -e '/[       ]_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT[    ]/d' \
            < ${CONFIG_HEADER} >> $@ ;\
so for many macros one needs _GLIBCXX_ prefixes already in configure,
as can be seen in grep AC_DEFINE.*_GLIBCXX configure.ac acinclude.m4
But _GLIBCXX_HAVE_POSIX_SEMAPHORE is the only one that shouldn't have
that prefix because the sed is adding that.
E.g. on i686-linux, I see
grep _GLIBCXX__GLIBCXX c++config.h 
#define _GLIBCXX__GLIBCXX_HAVE_POSIX_SEMAPHORE 1
that proves it is the only broken one.

So, I think the right fix is:

2021-04-21  Jakub Jelinek  <jakub@redhat.com>

	PR libstdc++/100164
	* acinclude.m4: For POSIX semaphores AC_DEFINE HAVE_POSIX_SEMAPHORE
	rather than _GLIBCXX_HAVE_POSIX_SEMAPHORE.
	* configure: Regenerated.
	* config.h.in: Regenerated.

--- libstdc++-v3/acinclude.m4.jj	2020-12-16 14:42:46.501084530 +0100
+++ libstdc++-v3/acinclude.m4	2021-04-21 10:51:52.450419650 +0200
@@ -4097,7 +4097,7 @@ AC_DEFUN([GLIBCXX_CHECK_GTHREADS], [
       [ac_have_posix_semaphore=no])
 
   if test $ac_have_posix_semaphore = yes ; then
-    AC_DEFINE(_GLIBCXX_HAVE_POSIX_SEMAPHORE,
+    AC_DEFINE(HAVE_POSIX_SEMAPHORE,
 	      1,
 	      [Define to 1 if POSIX Semaphores with sem_timedwait are available in <semaphore.h>.])
   fi
--- libstdc++-v3/configure.jj	2021-04-09 10:18:15.701265030 +0200
+++ libstdc++-v3/configure	2021-04-21 10:52:06.730259672 +0200
@@ -75836,7 +75836,7 @@ fi
 
   if test $ac_have_posix_semaphore = yes ; then
 
-$as_echo "#define _GLIBCXX_HAVE_POSIX_SEMAPHORE 1" >>confdefs.h
+$as_echo "#define HAVE_POSIX_SEMAPHORE 1" >>confdefs.h
 
   fi
   { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_have_posix_semaphore" >&5
--- libstdc++-v3/config.h.in.jj	2020-12-17 16:06:39.808526661 +0100
+++ libstdc++-v3/config.h.in	2021-04-21 10:52:09.709226370 +0200
@@ -291,6 +291,10 @@
 /* Define to 1 if you have the `posix_memalign' function. */
 #undef HAVE_POSIX_MEMALIGN
 
+/* Define to 1 if POSIX Semaphores with sem_timedwait are available in
+   <semaphore.h>. */
+#undef HAVE_POSIX_SEMAPHORE
+
 /* Define to 1 if you have the `powf' function. */
 #undef HAVE_POWF
 
@@ -818,10 +822,6 @@
 /* Define if gthreads library is available. */
 #undef _GLIBCXX_HAS_GTHREADS
 
-/* Define to 1 if POSIX Semaphores with sem_timedwait are available in
-   <semaphore.h>. */
-#undef _GLIBCXX_HAVE_POSIX_SEMAPHORE
-
 /* Define to 1 if a full hosted library is built, or 0 if freestanding. */
 #undef _GLIBCXX_HOSTED
 


	Jakub