-pie was added to C flags for ThreadSanitizer in commit 19f251a2882a8d0779b432e63bf282e4d9c443bb. Under clang 3.8.0, the -pie flag causes a compiler warning and a linker error when running configure --toolchain=clang-tsan. Here is an excerpt from config.log:
clang ... -fsanitize=thread -pie -std=c11 -fomit-frame-pointer -pthread -c -o /tmp/ffconf.hL61stP9.o /tmp/ffconf.YO6ZaSFG.c clang: warning: argument unused during compilation: '-pie' clang -fsanitize=thread -pie -Wl,--as-needed -Wl,-z,noexecstack -o /tmp/ffconf.W5c2e41l /tmp/ffconf.hL61stP9.o -lbz2 -pthread /usr/bin/ld: /tmp/ffconf.hL61stP9.o: relocation R_X86_64_PC32 against undefined symbol `atan2f@@GLIBC_2.2.5' can not be used when making a shared object; recompile with -fPIC /usr/bin/ld: final link failed: Bad value clang: error: linker command failed with exit code 1 (use -v to see invocation) To be conservative, I changed -pie to -fPIE. But the documentation seems to imply just -fsanitize=thread is enough: http://clang.llvm.org/docs/ThreadSanitizer.html https://github.com/google/sanitizers/wiki/ThreadSanitizerCppManual Signed-off-by: Wan-Teh Chang <w...@google.com> --- configure | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/configure b/configure index ee473b9..0e1ae61 100755 --- a/configure +++ b/configure @@ -3523,7 +3523,7 @@ case "$toolchain" in ;; *-tsan) cc_default="${toolchain%-tsan}" - add_cflags -fsanitize=thread -pie + add_cflags -fsanitize=thread -fPIE add_ldflags -fsanitize=thread -pie case "$toolchain" in gcc-tsan) -- 2.8.0.rc3.226.g39d4020 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
