https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120653
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |fw at gcc dot gnu.org
Component|tree-optimization |libgcc
Keywords| |wrong-code
--- Comment #4 from Sam James <sjames at gcc dot gnu.org> ---
I can reproduce in a vanilla fedora:41 container (=> no spec or default
patching; should really consider that on our end too) with just build deps
installed, then with the glibc-2.41 tarball:
```
$ mkdir /tmp/build && cd /tmp/build
$ /tmp/glibc-2.41/configure --prefix=/usr
$ make -j$(nproc) -l$(nproc)
$ make -j$(nproc) -l$(nproc) check
[...]
=== Summary of results ===
5 FAIL
6008 PASS
122 UNSUPPORTED
16 XFAIL
4 XPASS
```
Those are harmless and related to the container.
Then:
```
$ mkdir /tmp/build-mangled && cd /tmp/build-mangled
$ /tmp/glibc-2.41/configure --prefix=/usr CFLAGS="-O2 -fno-strict-aliasing"
$ make -j$(nproc) -l$(nproc)
$ make -j$(nproc) -l$(nproc) check
[...]
=== Summary of results ===
130 FAIL
5883 PASS
122 UNSUPPORTED
16 XFAIL
4 XPASS
$ grep ^FAIL tests.sum | grep back
FAIL: debug/backtrace-tst
FAIL: debug/tst-backtrace2
FAIL: debug/tst-backtrace3
FAIL: debug/tst-backtrace4
FAIL: debug/tst-backtrace5
FAIL: debug/tst-backtrace6
FAIL: nptl/tst-backtrace1
```
