/usr/lib/libc.so is a linker script that used to contain: GROUP ( /lib/libc.so.7 /usr/lib/libc_nonshared.a /usr/lib/libssp_nonshared.a ) In r266227 /usr/lib/libc.so was changed to avoid including full paths: GROUP ( libc.so.7 libc_nonshared.a libssp_nonshared.a ) Using lld (LLVM's linker) on FreeBSD fails due to this, as it does not have built-in search paths and relies on the compiler driver to pass in the expected paths via -L arguments. Clang currently passes only -L /usr/lib, as this is the only path that "should" be required at link time. We may be able to restore the paths and use the --sysroot argument to ld.
Most recent buildworld-with-lld attempt was reported here: http://lists.llvm.org/pipermail/llvm-dev/2016-March/096449.html > 3. Library search paths > > In FreeBSD /usr/lib/libc.so is a linker script that contains > "GROUP ( libc.so.7 libc_nonshared.a libssp_nonshared.a )". ld.bfd > includes a built-in /lib search path and finds /lib/libc.so.7 there. > lld relies only on the -L paths specified on the command line, and > cannot locate libc.so.7. As a workaround I've changed /usr/lib/libc.so > to include the full path.
A commit references this bug: Author: bdrewery Date: Tue Mar 15 22:27:30 UTC 2016 New revision: 296921 URL: https://svnweb.freebsd.org/changeset/base/296921 Log: Partially revert r266227 and stop stripping paths in ldscripts. Specifically this fixes /usr/lib/libc.so stripping the paths to the libraries. The reason for this in r266227 was both likely because ld(1) did not fully respect --sysroot until r291226 and because of the lib32 build. The lib32 build does not use --sysroot into the /usr/lib32 path, rather it only uses -L and -B into the /usr/lib32 path and --sysroot into the normal (64bit) /usr/lib. The _LDSCRIPTROOT was added with the ldscript support in bsd.lib.mk so that it builds a 32-bit-sysrooted pathed ldscript in the object directory and then installs a normal unprefixed version in installworld. This commit also fixes the rebuild during install which was broken in r266227. This commit would break DIRDEPS_BUILD build of lib32 but it does not currently have a way to build it anyhow. For example, before this change we had in /usr/lib/libc.so: GROUP ( libc.so.7 libc_nonshared.a libssp_nonshared.a ) Now it is restored to pre-r266227: GROUP ( /lib/libc.so.7 /usr/lib/libc_nonshared.a /usr/lib/libssp_nonshared.a ) The motivation for this is in testing of lld. From emaste: lld does not have built-in search paths (e.g. /lib, /usr/lib) and relies on -L arguments passed by the caller. As the linker is nearly always invoked from the clang driver this is fine other than the fact that /usr/lib/libc.so is an ldscript that refers to libc.so.7 which is in /lib, not /usr/lib. PR: 207980 Reported by: emaste Submitted by: emaste (based on) Differential Revision: https://reviews.freebsd.org/D5637 Changes: head/share/mk/bsd.lib.mk head/share/mk/bsd.sys.mk