[Emacs-diffs] trunk r113775: Define a few variables of obscure types to aid debugging exceptions on Windows.

[Eli Zaretskii]

------------------------------------------------------------
revno: 113775
revision-id: address@hidden
parent: address@hidden
fixes bug: http://debbugs.gnu.org/15024
committer: Eli Zaretskii <address@hidden>
branch nick: trunk
timestamp: Fri 2013-08-09 13:18:48 +0300
message:
  Define a few variables of obscure types to aid debugging exceptions on 
Windows.
  
   src/w32.c (PEXCEPTION_POINTERS, PEXCEPTION_RECORD, PCONTEXT): Define
   variables of these types so that GDB would know about them, as aid
   for debugging fatal exceptions.  (Bug#15024)  See also
   http://sourceware.org/ml/gdb/2013-08/msg00010.html for related
   discussions.
modified:
  src/ChangeLog                  changelog-20091113204419-o5vbwnq5f7feedwu-1438
  src/w32.c                      w32.c-20091113204419-o5vbwnq5f7feedwu-808

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2013-08-08 17:52:00 +0000
+++ b/src/ChangeLog     2013-08-09 10:18:48 +0000
@@ -1,3 +1,11 @@
+2013-08-09  Eli Zaretskii  <address@hidden>
+
+       * w32.c (PEXCEPTION_POINTERS, PEXCEPTION_RECORD, PCONTEXT): Define
+       variables of these types so that GDB would know about them, as aid
+       for debugging fatal exceptions.  (Bug#15024)  See also
+       http://sourceware.org/ml/gdb/2013-08/msg00010.html for related
+       discussions.
+
 2013-08-08  Jan Djärv  <address@hidden>
 
        * nsterm.m (ns_update_begin): Don't change clip path if it would be

=== modified file 'src/w32.c'
--- a/src/w32.c 2013-08-04 15:43:10 +0000
+++ b/src/w32.c 2013-08-09 10:18:48 +0000
@@ -89,6 +89,21 @@
   DWORDLONG ullAvailExtendedVirtual;
 } MEMORY_STATUS_EX,*LPMEMORY_STATUS_EX;
 
+/* These are here so that GDB would know about these data types.  This
+   allows to attach GDB to Emacs when a fatal exception is triggered
+   and Windows pops up the "application needs to be closed" dialog.
+   At that point, _gnu_exception_handler, the top-level exception
+   handler installed by the MinGW startup code, is somewhere on the
+   call-stack of the main thread, so going to that call frame and
+   looking at the argument to _gnu_exception_handler, which is a
+   PEXCEPTION_POINTERS pointer, can reveal the exception code
+   (excptr->ExceptionRecord->ExceptionCode) and the address where the
+   exception happened (excptr->ExceptionRecord->ExceptionAddress), as
+   well as some additional information specific to the exception.  */
+PEXCEPTION_POINTERS excptr;
+PEXCEPTION_RECORD excprec;
+PCONTEXT ctxrec;
+
 #include <lmcons.h>
 #include <shlobj.h>