Re: [PATCH v3] [gdb/testsuite] New test: gdb.base/check-errno.exp

[Kevin Buettner <kevinb@redhat.com>]

On Thu, 2 May 2024 12:37:23 +0200
Tom de Vries <tdevries@suse.de> wrote:

> On 5/2/24 03:38, Kevin Buettner wrote:
> > Printing the value of 'errno' from GDB is sometimes problematic.  The
> > situation has improved in recent years, though there are still
> > scenarios for which "print errno" doesn't work.
> > 
> > The test, gdb.base/check-errno.exp, introduced by this commit,
> > tests whether or not GDB can print errno with a binary compiled
> > in the following different ways:
> > 
> > - default: no switches aside from -g (and whatever else is added by the
> >    testing framework)
> > - macros: macros included in the debuginfo; this is enabled by using
> >    -g3 when using gcc or clang
> > - static: statically linked binary
> > - static-macros: statically linked binary w/ macro definitions included
> >    in debuginfo
> > - pthreads: libpthread linked binary
> > - pthreads-macros: libpthread linked binary w/ macro definitions included
> >    in debuginfo
> > - pthreads-static: Statically linked against libpthread
> > - pthreads-static-macros: Statically linked against libpthread w/ macro
> >    definitions  
> 
> Hi,
> 
> I applied the patch, and ran the test-case on leap 15.5.
> 
> With glibc debuginfo installed, I get:
> ...
> FAIL: gdb.base/check-errno.exp: default: print errno
> FAIL: gdb.base/check-errno.exp: default: print (int) errno
> FAIL: gdb.base/check-errno.exp: default: check errno value from corefile
> FAIL: gdb.base/check-errno.exp: static: print errno
> FAIL: gdb.base/check-errno.exp: static: check errno value from corefile
> FAIL: gdb.base/check-errno.exp: pthreads-static: print errno
> FAIL: gdb.base/check-errno.exp: pthreads-static: check errno value from 
> corefile
> ...
> 
> Without glibc debuginfo installed, I get:
> ...
> FAIL: gdb.base/check-errno.exp: default: print (int) errno
> FAIL: gdb.base/check-errno.exp: static: print errno
> FAIL: gdb.base/check-errno.exp: static: check errno value from corefile
> FAIL: gdb.base/check-errno.exp: pthreads-static: print errno
> FAIL: gdb.base/check-errno.exp: pthreads-static: check errno value from 
> corefile
> ...
> 
> Then I ran it on tumbleweed.
> 
> With and without glibc debuginfo installed, I get:
> ...
> FAIL: gdb.base/check-errno.exp: static: print errno
> FAIL: gdb.base/check-errno.exp: static: check errno value from corefile
> FAIL: gdb.base/check-errno.exp: pthreads-static: print errno
> FAIL: gdb.base/check-errno.exp: pthreads-static: check errno value from 
> corefile
> ...
> 
> Looking in more detail at the first two FAILs of leap 15.5 with glibc 
> debug info installed, we have:
> ...
> (gdb) print errno^M
> Cannot find thread-local storage for process 2259, shared library 
> /lib64/libc.so.6:^M
> Cannot find thread-local variables on this target^M
> (gdb) FAIL: gdb.base/check-errno.exp: default: print errno
> print (int) errno^M
> Cannot find thread-local storage for process 2259, shared library 
> /lib64/libc.so.6:^M
> Cannot find thread-local variables on this target^M
> (gdb) FAIL: gdb.base/check-errno.exp: default: print (int) errno
> ...
> 
> I think some of these are FAILs due to using a glibc version that 
> doesn't have libpthreads merged.  Leap 15.5 uses glibc 2.31. 
> libpthreads was merged into libc in version 2.34.  Current tumbleweed 
> uses 2.39.

I can reproduce some of the above using old versions of Fedora.  I'll
attempt to xfail those cases too.

> FWIW, in a fedora rawhide container I get:
> ...
> XPASS: gdb.base/check-errno.exp: static-macros: print (int) errno
> XPASS: gdb.base/check-errno.exp: pthreads-static-macros: print (int) errno
> ...
> 
> That matches your description, but I think these xpasses shouldn't be there.

Based on bug 31693, which you recently filed, I agree.  Those should 
be FAILs.  I'll update it so that those tests fail instead.

Thanks!

Kevin