If multiple files with the same build id were found, we silently randomly
overwrote one with the other.
Change the order to make the output deterministic, and emit a
warning when overwriting.
Currently, separate-debug-info adds a debug output, and the build fail when it is
not created. the output is only created when at least one elf file is
stripped.
As a result, adding separateDebugInfo = true on a lib will break the
static build (unless the lib also contains an executable). In order to
not have to remember to add an exception every time, let's just create
the debug output unconditionally.
Before the change separate-debug-info.sh did the stripping itself.
This scheme has a few problems:
1. Stripping happens only on ELF files. *.a and *.o files are skipped.
Derivations have to do it manually. Usually incorrectly
as they don't run $RANLIB (true for `glibc` and `musl`).
2. Stripping happens on all paths. Ideally only `stripDebugList` paths
should be considered.
3. Host strip is called on Target files.
This change offloads stripping logic to strip hook. This strips more
files for `glibc` and `musl`. Now we can remove most $STRIP calls
from individual derivations.
Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
By default, Cargo will only enable line tables. -g enables full debug
info. The RUSTFLAGS environment variable is examined by Cargo,
similar to how the NIX_*FLAGS* variables are examined by our compiler
wrappers.
This reverts commit 848091a52b, reversing
changes made to ab0e692ac7.
It caused issues with elfutils tests,
probably through over-stripping of glibc parts.
According to https://stackoverflow.com/q/46197810/115030,
--only-keep-debug preserves all the information stripped by
--strip-unneeded. This reduces the size of the webkitgtk output by 22%
(123 MB → 96 MB).
Inspired by #159612.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
find fails when called with an inexistent search path.
That situation may arise when the output is created after by a postFixup hook.
vcunat amended the PR by clarifying one more `return` to `return 0`.
The importance of glibc makes it worthwhile to provide debug
symbols. However, this revealed an issue with separateDebugInfo: it
was indiscriminately adding --build-id to all ld invocations, while in
fact it should only do that for final links. Glibc also uses non-final
("relocatable") links, leading to subsequent failure to apply a build
ID ("Cannot create .note.gnu.build-id section, --build-id
ignored"). So now ld-wrapper.sh only passes --build-id for final
links.
For instance, a binary like libfoo.so will cause a symlink
lib/debug/libfoo.so.debug -> .build-id/<build-ID>.debug to be
created. This is primarily useful for use with eu-addr2line, if you
know the name of a binary and the relative address, but not the build
ID.
You can now pass
separateDebugInfo = true;
to mkDerivation. This causes debug info to be separated from ELF
binaries and stored in the "debug" output. The advantage is that it
enables installing lean binaries, while still having the ability to
make sense of core dumps, etc.
