On Thu, 2021-11-25 at 11:26 -0500, Ken Brown via Cygwin-apps wrote: > On 9/29/2021 7:46 PM, Brian Inglis wrote: > > There is a gnulib bug in threadlib.m4 from at least serial 29 to serial > > 31 that incorrectly configures Cygwin support of weak references. > > > > This leads to SIGSEGV stack smashing crashes with no backtrace > > @ 0x00000000100000000 or 0x0000000500000000 etc. normally during tests. > > > > Akim Demaille on bug-bison referred the issue to bug-gnulib where > > Bruno Haible diagnosed and patched the problem to appear in > > m4/threadlib.m4 serial 32: > > > > * m4/threadlib.m4 (gl_WEAK_SYMBOLS): Force a "guessing no" result on > > Cygwin > > https://lists.gnu.org/archive/html/bug-gnulib/2021-09/msg00068.html > > [gl_cv_have_weak="guessing no"] > > > > The patch has now been applied to bison, wget, and wget2, and I have > > attached my patches for the copies in those packages, in case anyone > > else has this issue in their (mainly GNU) packages which may incorporate > > by > > inclusion recently updated gnulib m4 macros used in autotools builds. > > Thanks, Brian. > > I'm writing to reinforce this warning. I just spent 2 days trying to debug > mysterious texinfo crashes that were caused by this bug. I could have saved > a > lot of time if I had remembered your email and had checked the gnulib > version > being used by texinfo. > > For anyone else who bumps into this, gdb and strace are of no use in > debugging > this crash. I finally thought to look at the stackdump file, and the second > address from the top was in a gnulib file. That was the key clue.
Add gl_cv_have_weak=no to cygconf? -- Yaakov
