diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4 index c2977e4c375f004b1559cb937997f7497312c684..49cb0623e4f04665645b7ef2f0132bced452a892 100644 --- a/libstdc++-v3/acinclude.m4 +++ b/libstdc++-v3/acinclude.m4 @@ -5290,6 +5290,33 @@ AC_DEFUN([GLIBCXX_CHECK_ALIGNAS_CACHELINE], [ AC_LANG_RESTORE ]) +dnl +dnl Check whether iostream initialization should be done in the library, +dnl using the init_priority attribute. +dnl +dnl Defines: +dnl _GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE if GCC supports the init_priority +dnl attribute for the target. +dnl +AC_DEFUN([GLIBCXX_CHECK_INIT_PRIORITY], [ +AC_LANG_SAVE + AC_LANG_CPLUSPLUS + + AC_MSG_CHECKING([whether init_priority attribute is supported]) + AC_TRY_COMPILE(, [ + #if ! __has_attribute(init_priority) + #error init_priority not supported + #endif + ], [ac_init_priority=yes], [ac_init_priority=no]) + if test "$ac_init_priority" = yes; then + AC_DEFINE_UNQUOTED(_GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE, 1, + [Define if init_priority should be used for iostream initialization.]) + fi + AC_MSG_RESULT($ac_init_priority) + + AC_LANG_RESTORE +]) + # Macros from the top-level gcc directory. m4_include([../config/gc++filt.m4]) m4_include([../config/tls.m4]) diff --git a/libstdc++-v3/config.h.in b/libstdc++-v3/config.h.in index 047dcc4f1ddce451160fa9da707ac65a04935e50..7129adfad541851dea61619bd56c346ed5b8ac5d 100644 --- a/libstdc++-v3/config.h.in +++ b/libstdc++-v3/config.h.in @@ -958,6 +958,9 @@ /* Define if get_nprocs is available in <sys/sysinfo.h>. */ #undef _GLIBCXX_USE_GET_NPROCS +/* Define if init_priority should be used for iostream initialization. */ +#undef _GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE + /* Define if LFS support is available. */ #undef _GLIBCXX_USE_LFS diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure index 5339834b8756578c6e99d7b80a85d9f9952f0b7c..9b6027775456469940da9c515dad5c0160d3cd3d 100755 --- a/libstdc++-v3/configure +++ b/libstdc++-v3/configure @@ -71732,6 +71732,57 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu +# For using init_priority in ios_init.cc + + + ac_ext=cpp +ac_cpp='$CXXCPP $CPPFLAGS' +ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5' +ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5' +ac_compiler_gnu=$ac_cv_cxx_compiler_gnu + + + { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether init_priority attribute is supported" >&5 +$as_echo_n "checking whether init_priority attribute is supported... " >&6; } + cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +int +main () +{ + + #if ! __has_attribute(init_priority) + #error init_priority not supported + #endif + + ; + return 0; +} +_ACEOF +if ac_fn_cxx_try_compile "$LINENO"; then : + ac_init_priority=yes +else + ac_init_priority=no +fi +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext + if test "$ac_init_priority" = yes; then + +cat >>confdefs.h <<_ACEOF +#define _GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE 1 +_ACEOF + + fi + { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_init_priority" >&5 +$as_echo "$ac_init_priority" >&6; } + + ac_ext=c +ac_cpp='$CPP $CPPFLAGS' +ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5' +ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5' +ac_compiler_gnu=$ac_cv_c_compiler_gnu + + + # Define documentation rules conditionally. # See if makeinfo has been installed and is modern enough diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac index df01f58bd83d0e3c5fc8d35d80b08e3b41c40d91..91b3c1f32f2a8ccd7c5c7c35353442fbbc01be96 100644 --- a/libstdc++-v3/configure.ac +++ b/libstdc++-v3/configure.ac @@ -541,6 +541,9 @@ GLIBCXX_ZONEINFO_DIR # For src/c++11/shared_ptr.cc alignment. GLIBCXX_CHECK_ALIGNAS_CACHELINE +# For using init_priority in ios_init.cc +GLIBCXX_CHECK_INIT_PRIORITY + # Define documentation rules conditionally. # See if makeinfo has been installed and is modern enough diff --git a/libstdc++-v3/include/std/iostream b/libstdc++-v3/include/std/iostream index cfd124dcf432e40b7151be2e4660297b4cb05082..0abf7445f58b960c7f35db75f31f211642fe4900 100644 --- a/libstdc++-v3/include/std/iostream +++ b/libstdc++-v3/include/std/iostream @@ -75,7 +75,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // For construction of filebuffers for cout, cin, cerr, clog et. al. // When the init_priority attribute is usable, we do this initialization // in the compiled library instead (src/c++98/globals_io.cc). -#if !__has_attribute(__init_priority__) +#if !(_GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE \ + && __has_attribute(__init_priority__)) static ios_base::Init __ioinit; #elif defined(_GLIBCXX_SYMVER_GNU) __extension__ __asm (".globl _ZSt21ios_base_library_initv"); diff --git a/libstdc++-v3/src/c++98/ios_base_init.h b/libstdc++-v3/src/c++98/ios_base_init.h index b600ec3298e45f252a8231a087be911a4aaefc66..f7edfc846258db6b3ad5a5f478bbc15182db0d8c 100644 --- a/libstdc++-v3/src/c++98/ios_base_init.h +++ b/libstdc++-v3/src/c++98/ios_base_init.h @@ -8,6 +8,6 @@ // constructor when statically linking with libstdc++.a), instead of // doing so in (each TU that includes) <iostream>. // This needs to be done in the same TU that defines the stream objects. -#if __has_attribute(init_priority) +#if _GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE static ios_base::Init __ioinit __attribute__((init_priority(90))); #endif