c11/threads: resolve link issues with -O0
Add weak symbol notation for the pthread_mutexattr* symbols, thus making
the linker happy. When building with -O1 or greater the optimiser will
kick in and remove the said functions as they are dead/unreachable code.
Ideally we'll enable the optimisations locally, yet that does not seem
to work atm.
v2: Add the AX_GCC_FUNC_ATTRIBUTE([weak]) hunk in configure.
Cc: Alejandro Piñeiro <apinheiro@igalia.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Tested-by: Mark Janes <mark.a.janes@intel.com>
diff --git a/configure.ac b/configure.ac
index 47c138a..fc0b1db 100644
--- a/configure.ac
+++ b/configure.ac
@@ -233,6 +233,7 @@
AX_GCC_FUNC_ATTRIBUTE([returns_nonnull])
AX_GCC_FUNC_ATTRIBUTE([unused])
AX_GCC_FUNC_ATTRIBUTE([warn_unused_result])
+AX_GCC_FUNC_ATTRIBUTE([weak])
AM_CONDITIONAL([GEN_ASM_OFFSETS], test "x$GEN_ASM_OFFSETS" = xyes)