With linker sections GC enabled, we get a test failure in `nlist.c`:
```
nlist: nlist.c:72: main: Assertion `rc == 0' failed.
```
This turns out to be because several sections used by the test can be discarded:
```
ld: removing unused section '.text.func_pub' in file 'nlist.o'
ld: removing unused section '.bss.data_pub_uninit' in file 'nlist.o'
ld: removing unused section '.data.data_pub_init' in file 'nlist.o'
```
Reproduced with `CFLAGS="-Og -fdata-sections -ffunction-sections"` and
`LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,--gc-sections -Wl,-z,start-stop-gc"`.
Additionally, `LDFLAGS="... -Wl,--print-gc-sections"` can help with diagnosing
which sections get removed.
We already mark these symbols as `used`, but we need `retain` [0] for them
to survive linker GC too.
[0] https://releases.llvm.org/18.1.0/tools/lld/docs/ELF/start-stop-gc.html#annotate-c-identifier-name-sectionsCloses: !29
Signed-off-by: Sam James <sam@gentoo.org>
Signed-off-by: Guillem Jover <guillem@hadrons.org>
Because some of the symbols are not otherwise referenced, GCC would like
to remove them.
Closes: !14
Signed-off-by: Guillem Jover <guillem@hadrons.org>
Commit e8d340de ("Remove a.out support from nlist()") introduced a copy
of the definition of nlist from a.out.h. However, as well as having
n_name inside n_un, on the various BSDs n_name could also be accessed
as a direct member of nlist, and this is made use of by FreeBSD's
usr.bin/netstat/main.c. Thus we should also add the same enclosing
anonymous union.
[guillem@hadrons.org:
- Add a minimal unit test. ]
Closes: !4
Signed-off-by: Guillem Jover <guillem@hadrons.org>
On IA64 this is only the case in the ELF binary, but it gets normalized
when loaded at run-time.
Fixes: https://bugs.debian.org/881611
Signed-off-by: Guillem Jover <guillem@hadrons.org>
At least on IA64 and PowerPC 64-bit ELFv1, the functions are stored in
the .text sections but they are accessed through a function descriptor
stored in a data section, for example for PowerPC 64-bit ELFv1 that
section is called .opd.
We should take this into account when checking the n_type for the
functions we have requested information from nlist().
Rationale-by: James Clarke <jrtc27@jrtc27.com>
