As uncovered by PR testsuite/125310, libcaf_shmem isn't built on
Solaris. This happens because the AX_PTHREAD autoconf macro erroneously
thinks that Solaris lacks pthreads support.
The problem is that the macros expects _REENTRANT to be defined in
multithreaded programs. However, as described in
https://gcc.gnu.org/gcc-16/porting_to.html#solaris the Solaris 11.4
system headers no longer reference _REENTRANT, so GCC 16 doesn't define
it any longer.
The issue is still present in current ax_pthread.m4 (serial 31) in the
autoconf archive. This patch fixes this by only requiring _REENTRANT in
older Solaris versions that still need it by checking for pre-XPG7
system headers.
Bootstrapped without regressions on i386-pc-solaris2.11 and
sparc-sun-solaris2.11. Also tested manually on Solaris 11.3.
Ok for trunk?
Rainer
--
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University
2026-05-14 Rainer Orth <[email protected]>
config:
* ax_pthread.m4 (ax_pthread_check_macro) <solaris*>: Only require
_REENTRANT before Solaris 11.4
libgfortran:
* configure: Regenerate.
# HG changeset patch
# Parent 8ee4b3f549ede67c2b3e8c7e5c6cf3e1ec99fd7f
config: Fix ax_pthread.m4 on Solaris 11.4
diff --git a/config/ax_pthread.m4 b/config/ax_pthread.m4
--- a/config/ax_pthread.m4
+++ b/config/ax_pthread.m4
@@ -208,7 +208,22 @@ AS_IF([test "x$GCC" = "xyes"],
# correctly enabled
case $host_os in
- darwin* | hpux* | linux* | osf* | solaris*)
+ solaris*)
+ # Solaris 11.4 introduced XPG7 support and did away with the need for
+ # _REENTRANT.
+
+ AC_EGREP_CPP([AX_PTHREAD_SOLARIS__REENTRANT],
+ [
+# undef _XOPEN_SOURCE
+# include <sys/feature_tests.h>
+# if _XOPEN_VERSION < 700
+ AX_PTHREAD_SOLARIS__REENTRANT
+# endif
+ ],
+ [ax_pthread_check_macro="_REENTRANT"],
+ [ax_pthread_check_macro="--"])
+ ;;
+ darwin* | hpux* | linux* | osf*)
ax_pthread_check_macro="_REENTRANT"
;;
diff --git a/libgfortran/configure b/libgfortran/configure
--- a/libgfortran/configure
+++ b/libgfortran/configure
@@ -17917,7 +17917,30 @@ fi
# correctly enabled
case $host_os in
- darwin* | hpux* | linux* | osf* | solaris*)
+ solaris*)
+ # Solaris 11.4 introduced XPG7 support and did away with the need for
+ # _REENTRANT.
+
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+# undef _XOPEN_SOURCE
+# include <sys/feature_tests.h>
+# if _XOPEN_VERSION < 700
+ AX_PTHREAD_SOLARIS__REENTRANT
+# endif
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+ $EGREP "AX_PTHREAD_SOLARIS__REENTRANT" >/dev/null 2>&1; then :
+ ax_pthread_check_macro="_REENTRANT"
+else
+ ax_pthread_check_macro="--"
+fi
+rm -f conftest*
+
+ ;;
+ darwin* | hpux* | linux* | osf*)
ax_pthread_check_macro="_REENTRANT"
;;
