diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 075442c124a..9f563dde665 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,5 +1,13 @@ 2020-02-26 Jonathan Wakely + Backport from mainline + 2020-01-28 Jonathan Wakely + + PR libstdc++/93325 + * acinclude.m4 (GLIBCXX_ENABLE_LIBSTDCXX_TIME): Use AC_SEARCH_LIBS for + clock_gettime instead of explicit glibc version check. + * configure: Regenerate. + Backport from mainline 2020-02-04 Jonathan Wakely diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4 index 3a9cd3cc162..d22e30230b3 100644 --- a/libstdc++-v3/acinclude.m4 +++ b/libstdc++-v3/acinclude.m4 @@ -1405,20 +1405,14 @@ AC_DEFUN([GLIBCXX_ENABLE_LIBSTDCXX_TIME], [ ac_has_sched_yield=yes ;; gnu* | linux* | kfreebsd*-gnu | knetbsd*-gnu) - AC_MSG_CHECKING([for at least GNU libc 2.17]) - AC_TRY_COMPILE( - [#include ], - [ - #if ! __GLIBC_PREREQ(2, 17) - #error - #endif - ], - [glibcxx_glibc217=yes], [glibcxx_glibc217=no]) - AC_MSG_RESULT($glibcxx_glibc217) - - if test x"$glibcxx_glibc217" = x"yes"; then - ac_has_clock_monotonic=yes - ac_has_clock_realtime=yes + # Don't use link test for freestanding library, in case gcc_no_link=yes + if test x"$is_hosted" = xyes; then + # Versions of glibc before 2.17 needed -lrt for clock_gettime. + AC_SEARCH_LIBS(clock_gettime, [rt]) + if test x"$ac_cv_search_clock_gettime" = x"none required"; then + ac_has_clock_monotonic=yes + ac_has_clock_realtime=yes + fi fi ac_has_nanosleep=yes ac_has_sched_yield=yes diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure index d2de3559af9..1225edc596b 100755 --- a/libstdc++-v3/configure +++ b/libstdc++-v3/configure @@ -21038,35 +21038,72 @@ ac_compiler_gnu=$ac_cv_cxx_compiler_gnu ac_has_sched_yield=yes ;; gnu* | linux* | kfreebsd*-gnu | knetbsd*-gnu) - { $as_echo "$as_me:${as_lineno-$LINENO}: checking for at least GNU libc 2.17" >&5 -$as_echo_n "checking for at least GNU libc 2.17... " >&6; } - cat confdefs.h - <<_ACEOF >conftest.$ac_ext + # Don't use link test for freestanding library, in case gcc_no_link=yes + if test x"$is_hosted" = xyes; then + # Versions of glibc before 2.17 needed -lrt for clock_gettime. + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing clock_gettime" >&5 +$as_echo_n "checking for library containing clock_gettime... " >&6; } +if ${ac_cv_search_clock_gettime+:} false; then : + $as_echo_n "(cached) " >&6 +else + ac_func_search_save_LIBS=$LIBS +cat confdefs.h - <<_ACEOF >conftest.$ac_ext /* end confdefs.h. */ -#include + +/* Override any GCC internal prototype to avoid an error. + Use char because int might match the return type of a GCC + builtin and then its argument prototype would still apply. */ +#ifdef __cplusplus +extern "C" +#endif +char clock_gettime (); int main () { - - #if ! __GLIBC_PREREQ(2, 17) - #error - #endif - +return clock_gettime (); ; return 0; } _ACEOF -if ac_fn_cxx_try_compile "$LINENO"; then : - glibcxx_glibc217=yes -else - glibcxx_glibc217=no +for ac_lib in '' rt; do + if test -z "$ac_lib"; then + ac_res="none required" + else + ac_res=-l$ac_lib + LIBS="-l$ac_lib $ac_func_search_save_LIBS" + fi + if test x$gcc_no_link = xyes; then + as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5 fi -rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext - { $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_glibc217" >&5 -$as_echo "$glibcxx_glibc217" >&6; } +if ac_fn_cxx_try_link "$LINENO"; then : + ac_cv_search_clock_gettime=$ac_res +fi +rm -f core conftest.err conftest.$ac_objext \ + conftest$ac_exeext + if ${ac_cv_search_clock_gettime+:} false; then : + break +fi +done +if ${ac_cv_search_clock_gettime+:} false; then : - if test x"$glibcxx_glibc217" = x"yes"; then - ac_has_clock_monotonic=yes - ac_has_clock_realtime=yes +else + ac_cv_search_clock_gettime=no +fi +rm conftest.$ac_ext +LIBS=$ac_func_search_save_LIBS +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_clock_gettime" >&5 +$as_echo "$ac_cv_search_clock_gettime" >&6; } +ac_res=$ac_cv_search_clock_gettime +if test "$ac_res" != no; then : + test "$ac_res" = "none required" || LIBS="$ac_res $LIBS" + +fi + + if test x"$ac_cv_search_clock_gettime" = x"none required"; then + ac_has_clock_monotonic=yes + ac_has_clock_realtime=yes + fi fi ac_has_nanosleep=yes ac_has_sched_yield=yes