configure.ac: fix libtool issue with clang and sanitizer
As pointed out at https://github.com/libexpat/libexpat/issues/312
libtool does not play nice with clang sanitizer builds at all.
For those builds LD shoud be set to clang too (and LDFLAGS needs the
sanitizer flags as well), because the clang compiler driver knows how
linking to the sanitizer libs works, but then at a later stage libtool
fails to actually produce the shared libraries and the build fails. This
is fixed by this patch.
Addtionally LD_LIBRARY_PATH has no effect on conftest runs during
configure time, so the rpath needs to be set to the asan library path to
ensure the configure run does not fail due to a missing asan library,
i.e.:
SANS='-fsanitize=memory -fsanitize-recover=all -shared-libsan'
export CC=clang-10
ASANPATH=$(dirname `$CC -print-file-name=libclang_rt.asan-x86_64.so`)
export LDFLAGS="-Wl,-rpath,$ASANPATH $SANS $LDFLAGS"
Change-Id: If3d9465068b2c654b935fc3d9ab41d799d5e02e8
diff --git a/configure.ac b/configure.ac
index 76c3515..b7b0d00 100644
--- a/configure.ac
+++ b/configure.ac
@@ -51,6 +51,11 @@
AC_PATH_PROG([RM_PROG], [rm])
AC_LANG([C++])
+dnl patching ${archive_cmds} to affect generation of file "libtool" to fix linking with clang
+AS_CASE(["$LD"],[*clang*],
+ [AS_CASE(["${host_os}"],
+ [*linux*],[archive_cmds='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-soname $wl$soname -o $lib'])])
+
dnl check for pkg-config (explained in detail in libosmocore/configure.ac)
AC_PATH_PROG(PKG_CONFIG_INSTALLED, pkg-config, no)
if test "x$PKG_CONFIG_INSTALLED" = "xno"; then