You can now build mold with the following commands:
$ mkdir -p out/debug
$ cd out/debug
$ cmake -GNinja -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_BUILD_TYPE=Debug ../..
$ ninja
To run tests, use the following commands:
$ cd out/debug
$ ctest -j$(nproc)
Previously, a GOT relocation (e.g. R_X86_64_REX_GOTPCRELX) and a
R_X86_64_64 relocation referring the same imported symbols were
resolved to different addresses. Here is why:
- When we saw a R_X86_64_64 relocation against an imported symbol,
we created a PLT and resolve the relocation there.
- GOT relocation is resolved to a GOT entry, which has a true
address of an imported function at runtime, which is different
from PLT entries that redirect calls to the real function.
With this patch, we no longer create a PLT entry for R_X86_64_64.
Instead, we emit a dynamic relocation so that it is always resolved
to a real function address.
Fixes GNU MP's `make check` failure, which was reported at
https://github.com/rui314/mold/issues/81
The grammar of the command is this
VERSION { <version-script> }
where <version-script> is a version script you can specify with
the --version-script option.
The default size and offsets of the .dynamic section are not necessarily
same with different builds of clang. For example, some builds can make
clang pass --hash-style=gnu to the linker and some --hash-style=both.
This change updates the test to compute the difference in size of the
.dynamic section before and after using the flag -spare-dynamic-tags,
making it independent of the compiler build.
Signed-off-by: Nehal J Wani <nehaljw.kkd1@gmail.com>
mold: /__w/mold/mold/test/tmp/pie/a.o:(.text): R_X86_64_32 relocation
against symbol `.rodata' can not be used; recompile with -fPIE
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Signed-off-by: Nehal J Wani <nehaljw.kkd1@gmail.com>
Previously, if a weak undefined symbol cannot be resolved within
an output of the linker, mold turned it into an absolute symbol
with value 0. However, other linkers export such symbols as a
weak dynamic symbol, so that the symbol gets another chance to be
resolved at runtime.
This patch implements the behavior.
This is needed by Gentoo's dev-libs/nsync-1.20.1 package.
This is needed by Gentoo's dev-lang/spidermonkey-78.10.1 package,
as its configure script assumes that the linker exit normally
even if extra options are given after `--version`.
We should not set STT_GNU_IFUNC to symbols in .dynsym because
from the other ELF module's point of view, it doens't matter
whether a symbol is IFUNC or not.
This is needed by Gentoo's sci-mathematics/nauty-2.6.7 package.
mmap(2) fails if you pass 0 as an argument for `length` parameter,
so this case has to be handled as a special case.
This is needed by Gentoo's media-plugins/calf-0.90.3-r1 package.
In other words, a linker shouldn't pull out an object file from an
archive to resolve an existing undefined or a common symbol with a
common symbol.
This is needed by Gentoo's app-arch/dump-0.4.47 package.
Previously, we turned unresolved undefined symbols into dynamic
symbols. This patch changed the behavior so that such symbols
are turned into non-dynamic absolute symbols with value zero.
This change is needed by Gentoo's dev-libs/wayland-protocols-1.21
package.
If an object file in an static archive contains a common symbol
that can be used to resolve an undefined symbol, mold now pulls
out that object file from the archive. Previously, we ignore such
common symbols.
Object files generated by a Fortran compiler often contain a lot of
common symbols, and this change makes a difference.
Fixes Gentoo's sci-astronomy/wcslib-7.3 package, which contains a
program written in Fortran.
