CFLAGS="-g -O2 -fno-optimize-sibling-calls" ./configure
+** Emacs compiled with GCC 4.6.1 crashes on MS-Windows when C-g is pressed
+
+This is known to happen when Emacs is compiled with MinGW GCC 4.6.1
+with the -O2 option (which is the default in the Windows build). The
+reason is a bug in MinGW GCC 4.6.1; to work around, either add the
+`-fno-omit-frame-pointer' switch to GCC or compile without
+optimizations (`--no-opt' switch to the configure.bat script).
+
** Emacs crashes in x-popup-dialog.
This can happen if the dialog widget cannot find the font it wants to
** Miscellaneous problems
+*** Editing files with very long lines is slow.
+
+For example, simply moving through a file that contains hundreds of
+thousands of characters per line is slow, and consumes a lot of CPU.
+This is a known limitation of Emacs with no solution at this time.
+
*** Emacs uses 100% of CPU time
This is a known problem with some versions of the Semantic package.
But in some of the cases listed above, this problem is a consequence
of something else that is wrong. Be sure to check and fix the real problem.
-*** Linux: Emacs crashes when dumping itself on Mac PPC running Yellow Dog GNU/Linux.
-
-The crashes happen inside the function Fmake_symbol; here's a typical
-C backtrace printed by GDB:
-
- 0x190c0c0 in Fmake_symbol ()
- (gdb) where
- #0 0x190c0c0 in Fmake_symbol ()
- #1 0x1942ca4 in init_obarray ()
- #2 0x18b3500 in main ()
- #3 0x114371c in __libc_start_main (argc=5, argv=0x7ffff5b4, envp=0x7ffff5cc,
-
-This could happen because GCC version 2.95 and later changed the base
-of the load address to 0x10000000. Emacs needs to be told about this,
-but we currently cannot do that automatically, because that breaks
-other versions of GNU/Linux on the MacPPC. Until we find a way to
-distinguish between the Yellow Dog and the other varieties of
-GNU/Linux systems on the PPC, you will have to manually uncomment the
-following section near the end of the file src/m/macppc.h in the Emacs
-distribution:
-
- #if 0 /* This breaks things on PPC GNU/Linux except for Yellowdog,
- even with identical GCC, as, ld. Let's take it out until we
- know what's really going on here. */
- /* GCC 2.95 and newer on GNU/Linux PPC changed the load address to
- 0x10000000. */
- #if defined __linux__
- #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
- #define DATA_SEG_BITS 0x10000000
- #endif
- #endif
- #endif /* 0 */
-
-Remove the "#if 0" and "#endif" directives which surround this, save
-the file, and then reconfigure and rebuild Emacs. The dumping process
-should now succeed.
-
*** OpenBSD 4.0 macppc: Segfault during dumping.
The build aborts with signal 11 when the command `./temacs --batch