From: Yann E. MORIN Date: Sat, 1 Oct 2016 19:04:47 +0000 (+0200) Subject: package.snappy: fix static builds with threads X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0e2ee0e6e8076;p=buildroot.git package.snappy: fix static builds with threads For some toolchains, libstdc++ uses pthread symbols: .../lib/libstdc++.a(eh_alloc.o): In function `__gnu_cxx::__mutex::lock()': eh_alloc.cc:(.text._ZN9__gnu_cxx7__mutex4lockEv[_ZN9__gnu_cxx7__mutex4lockEv]+0x2): undefined reference to `pthread_mutex_lock' and a lot of other pthread symbols... However, when doing a static build, there is no way for the linker to know what library to link in, so the build fails miserably if -pthread is not specified at link time. Fixes: http://autobuild.buildroot.org/results/15e/15ecaa23f0116e8120b3d62e553c838f0303df35/ http://autobuild.buildroot.org/results/f0a/f0abe301816e39eb4ae26d3e8cd42d90901d5ac5/ [Peter: only perform workaround if toolchain has threads support, tweak comment] Signed-off-by: "Yann E. MORIN" Signed-off-by: Peter Korsgaard --- diff --git a/package/snappy/snappy.mk b/package/snappy/snappy.mk index b00dddf6cf..6f89cf11cb 100644 --- a/package/snappy/snappy.mk +++ b/package/snappy/snappy.mk @@ -16,4 +16,13 @@ SNAPPY_INSTALL_STAGING = YES # Disable tests SNAPPY_CONF_OPTS = --disable-gtest +# libsnappy links with libstdc++. Some libstdc++/arch variants use +# pthread symbols for internal locking if built with thead +# support. libstdc++ does not have a .pc file, and its .la file does +# not mention -pthread. So, static linkig to libstdc++ will fail if +# -pthread is not explicity linked to. Only do that for static builds. +ifeq ($(BR2_STATIC_LIBS)$(BR2_TOOLCHAIN_HAS_THREADS),yy) +SNAPPY_CONF_OPTS += LIBS=-pthread +endif + $(eval $(autotools-package))