Script commands are processed before unused synthetic sections are
removed. Therefore, if a linker script matches one of these sections
it'll get emitted as an empty output section because the logic for
removing unused synthetic sections ignores script commands which
could have already matched and captured one of these sections. This
patch fixes that by also removing the unused synthetic sections from
the script commands.
Discussed with: dim
Obtained from: LLVM r307037
Sponsored by: The FreeBSD Foundation
This LLD commit was intended to fix one case of symbol versioning
(LLVM PR28414) but broke FreeBSD buildworld. It has been reverted
upstream in LLVM r306996.
Discussed with: dim
Given
.weak target
.global _start
_start:
b target
The intention is that the branch goes to the instruction after the
branch, effectively turning it on a nop. The branch adds the runtime
PC, but we were adding it statically too.
I noticed the oddity by inspection, but llvm-objdump seems to agree,
since it now prints things like:
b #-4 <_start+0x4>
Obtained from: LLD commit r305212
Differential Revision: https://reviews.freebsd.org/D11191
Reviewed by: dim, Rafael Espíndola
Obtained from: LLD r305212
MFC after: 3 days
No functional change; applied to facilitate merge of later LLD commit.
Reviewed by: dim, Rafael Espíndola
Obtained from: LLD r298797
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D11190
This change is a portion of LLD rev 305212 which accidentally ended
up in my svn tree. We do want to backport the change to LLD 4.0, but
it needs additional work and was not supposed to be included in
r319887.
If two sections contained relocations to absolute symbols with the same
value we would crash when trying to access their sections. Add a check that
both symbols point to sections before accessing their sections, and treat
absolute symbols as equal if their values are equal.
Obtained from: LLD commit r292578
MFC after: 3 days
GNU libtool checks the output from invoking the linker with --version
and --help, in order to determine the linker "flavour" and the command-
ine arguments to use for various link operations (e.g. generating shared
libraries). To detect GNU ld it looks for the strings "GNU" and
"supported targets:.*elf". Since LLD is compatible with GNU ld we
include those same strings to fool libtool.
Quoting from a comment in the change:
This is somewhat ugly hack, but in reality, we had no choice other
than doing this. Considering the very long release cycle of Libtool,
it is not easy to improve it to recognize LLD as a GNU compatible
linker in a timely manner. Even if we can make it, there are still a
lot of "configure" scripts out there that are generated by old
version of Libtool. We cannot convince every software developer to
migrate to the latest version and re-generate scripts. So we have
this hack.
Upstream LLVM revisions r298532, r298568, r298591
Obtained from: LLVM
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
The change was made to support glibc and believed to be a no-op on
FreeBSD, but that is not the case for architectures with multiple page
sizes, such as arm64. The relro p_memsz header was rounded up to the
default maximum page size (64K). When 4K pages are in use, multiple
pages beyond the final PT_LOAD segment had their permissions changed to
read-only after application of relocations and copy relocations, which
led to a segfault in certain cases.
This reverts upstream r290986. I have started a discussion about the
upstream fix on the LLVM mailing list.
Reported by: andrew
Sponsored by: The FreeBSD Foundation
