mingw GCC using ld.bfd emits diagnostics that include
"-plugin-opt=-pass-through=-lmoldname" and this triggers a match for
mold when it should not.
Instead, always check the very beginning of the output for the linker
id. This is pretty consistent:
- it is always on stdout
- GCC may put additional things on stderr we don't care about
- swift is bizarre and on some OSes redirects the linker stdout to
swiftc's stderr, but it will still be the only stderr; we didn't even
check stderr at all until commit 712cbe0568
For gold/bfd linkers, the linker id is always the *second* word, after
the legally mandated "GNU" we already check for.
[why]
Support for the relatively new mold linker is missing. If someone wants
to use mold as linker `LDFLAGS="-B/path/to/mold"` has to be added instead
of the usual `CC_LD=mold meson ...` or `CXX_LD=mold meson ...`.
[how]
Allow `mold' as linker for clang and newer GCC versions (that versions
that have support).
The error message can be a bit off, because it is generic for all GNU
like compilers, but I guess that is ok. (i.e. 'mold' is not listed as
possible linker, even if it would be possible for the given compiler.)
[note]
GCC Version 12.0.1 is not sufficient to say `mold` is supported. The
expected release with support will be 12.1.0.
On the other hand people that use the un-released 12.0.1 will probably
have built it from trunk. Allowing 12.0.1 is helping bleeding edge
developers to use mold in Meson already now.
Fixes: #9072
Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>
These are only used for type checking, so don't bother importing them at
runtime.
Generally add future annotations at the same time, to make sure that
existing uses of these imports don't need to be quoted.
e7c972b606
added PACKAGE_VENDOR to lld, causing the -v output to start with "Homebrew LLD"
rather than just "LLD". Meson no longer detects it and fails the
test_ld_environment_variable_lld unit test.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>