From: Fabrice Fontaine Date: Fri, 12 Oct 2018 22:15:02 +0000 (+0200) Subject: boost: context needs thread if gcc < 6 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=288b51719314eba2f7eb6101f1a4ed17b433ddad;p=buildroot.git boost: context needs thread if gcc < 6 Commit f3a483a81be43b0ff674400e11900605969f8f1c added -std=c++11 to boost build if context is selected and gcc is at least 4.7 however it has the side effect that cc-tool fails to find boost_system with the following error if context and system is enabled with a gcc greater than 6: configure:16312: /home/dawncrow/buildroot-test/scripts/instance-0/output/host/bin/x86_64-linux-g++ -o conftest -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I/home/dawncrow/buildroot-test/scripts/instance-0/output/host/x86_64-buildroot-linux-musl/sysroot/usr/include -L/home/dawncrow/buildroot-test/scripts/instance-0/output/host/x86_64-buildroot-linux-musl/sysroot/usr/lib conftest.o -lboost_system -latomic >&5 conftest.o: In function `boost::system::error_category::std_category::equivalent(int, std::error_condition const&) const': conftest.cpp:(.text._ZNK5boost6system14error_category12std_category10equivalentEiRKSt15error_condition[_ZNK5boost6system14error_category12std_category10equivalentEiRKSt15error_condition]+0x37): undefined reference to `boost::system::detail::generic_category_instance' This error is related to the fact that since boost 1.68 and commit https://github.com/boostorg/system/commit/7b6dcf6ac668e24f11ec5dbc68d1fa0248d964df, boost system headers are now C++14 "by default" with gcc above 6: - https://github.com/boostorg/system/issues/24 - https://github.com/boostorg/system/issues/26 - https://lists.boost.org/Archives/boost/2018/08/242770.php So when building with gcc > 6, cc-tool thinks that boost has generic_category_instance but because boost was compiled with std=c++11, this function will not be in the library causing a link error Instead of "hacking" even more boost, just remove -std=c++11 from boost.mk and select BOOST_THREAD with gcc lower than 6 Fixes: - http://autobuild.buildroot.org/results/fc8f8a64751c751b2b66301967cc008509bbaa70 Signed-off-by: Fabrice Fontaine Tested-by: Matt Weber Reviewed-by: Ferdinand van Aartsen Tested-by: Ferdinand van Aartsen Signed-off-by: Peter Korsgaard --- diff --git a/package/boost/Config.in b/package/boost/Config.in index e0bff17f75..0fe2422e5f 100644 --- a/package/boost/Config.in +++ b/package/boost/Config.in @@ -83,7 +83,7 @@ config BR2_PACKAGE_BOOST_CONTEXT bool "boost-context" depends on BR2_PACKAGE_BOOST_CONTEXT_ARCH_SUPPORTS depends on !BR2_TOOLCHAIN_HAS_GCC_BUG_64735 - select BR2_PACKAGE_BOOST_THREAD if !BR2_TOOLCHAIN_GCC_AT_LEAST_4_7 + select BR2_PACKAGE_BOOST_THREAD if !BR2_TOOLCHAIN_GCC_AT_LEAST_6 help C++11 context switching library. diff --git a/package/boost/boost.mk b/package/boost/boost.mk index 2ce6bbb75f..0adad89297 100644 --- a/package/boost/boost.mk +++ b/package/boost/boost.mk @@ -61,11 +61,6 @@ else BOOST_FLAGS += --without-icu endif -# boost-context needs C++11 -ifeq ($(BR2_PACKAGE_BOOST_CONTEXT)$(BR2_TOOLCHAIN_GCC_AT_LEAST_4_7),yy) -BOOST_TARGET_CXXFLAGS += -std=c++11 -endif - ifeq ($(BR2_PACKAGE_BOOST_IOSTREAMS),y) BOOST_DEPENDENCIES += bzip2 zlib endif