Please move this discussion to emacs-de...@gnu.org. > Date: Fri, 16 Aug 2013 01:59:41 -0400 > From: Ryan Johnson <ryan.john...@cs.utoronto.ca> > > The variable pending_exact has value 0x0, which would be a Bad Thing... > except that the code looks like this: > > if (!pending_exact > > > > /* If last exactn not at current position. */ > > => || pending_exact + *pending_exact + 1 != b > > > ... with corresponding assembly code looking very reasonable: > > 0x0000000100535cfa <regex_compile+34482>: cmpq $0x0,0x3f8(%rbp) > > 0x0000000100535d02 <regex_compile+34490>: je 0x100535eca > > <regex_compile+34946> > > 0x0000000100535d08 <regex_compile+34496>: mov 0x3f8(%rbp),%rax > > => 0x0000000100535d0f <regex_compile+34503>: movzbl (%rax),%eax > > 0x0000000100535d12 <regex_compile+34506>: movzbl %al,%eax > > 0x0000000100535d15 <regex_compile+34509>: lea 0x1(%rax),%rdx > > 0x0000000100535d19 <regex_compile+34513>: mov 0x3f8(%rbp),%rax > > 0x0000000100535d20 <regex_compile+34520>: add %rdx,%rax > > 0x0000000100535d23 <regex_compile+34523>: cmp %rbx,%rax > > 0x0000000100535d26 <regex_compile+34526>: jne 0x100535eca > > <regex_compile+34946>
What is the value in the RAX register at the point of the crash? Is it also zero? Or maybe it is some other invalid pointer value? > A third crash: > > #1 0x0000000100541930 in re_match_2_internal (bufp=0x10095ce20 > > <searchbufs+2912>, string1=0x0, size1=0, string2=0x6fffff00028 "-*- > > mode: compilation; default-directory: \"~/\" -*-\nCompilation started > > at Fri Aug 16 01:32:19\n\nls\n#message-20130808-090732#\t > > emacs-crash.txt\t\tmusic\n6b8ob06a.default.tar.xz\t\t > > emacs-nox.exe."..., size2=355, pos=254, regs=0x10095def0 > > <search_regs>, stop=317) at regex.c:6217 > > 6217 abort (); > This time, p (the subject of the case statement) points to 0x76b3b6c7, > which is the middle of a function (ntdll!RtlFillMemory, though the > memory map places that address smack in the middle of kernel32.dll > instead). This time it makes perfect sense that the switch statement > should fail, but how did p go so wrong? What is bufp->buffer at this point, and what is its contents? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
