* etc/PROBLEMS: Update Cygwin GCC information. (Bug#6458)

[bpt/emacs.git] / etc / PROBLEMS

diff --git a/etc/PROBLEMS b/etc/PROBLEMS
index db395df..7a2cc56 100644 (file)
--- a/etc/PROBLEMS
+++ b/etc/PROBLEMS
@@ -167,6 +167,17 @@ https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=239344
 
 * Crash bugs
 
+** Emacs crashes when running in a terminal, if compiled with GCC 4.5.0
+This version of GCC is buggy: see
+
+  http://debbugs.gnu.org/cgi/bugreport.cgi?bug=6031
+  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43904
+
+You can work around this error in gcc-4.5 by omitting sibling call
+optimization.  To do this, configure Emacs with
+
+ CFLAGS="-g -O2 -fno-optimize-sibling-calls" ./configure
+
 ** Emacs crashes in x-popup-dialog.
 
 This can happen if the dialog widget cannot find the font it wants to
@@ -2466,17 +2477,30 @@ files are installed. Then use:
 
 (using the location of the 32-bit X libraries on your system).
 
-*** Building the Cygwin port for MS-Windows can fail with some GCC versions
-
-Building Emacs 22 with Cygwin builds of GCC 3.4.4-1 and 3.4.4-2 is
-reported to either fail or cause Emacs to segfault at run time.  In
-addition, the Cygwin GCC 3.4.4-2 has problems with generating debug
-info.  Cygwin users are advised not to use these versions of GCC for
-compiling Emacs.  GCC versions 4.0.3, 4.0.4, 4.1.1, and 4.1.2
-reportedly build a working Cygwin binary of Emacs, so we recommend
-these GCC versions.  Note that these versions of GCC, 4.0.3, 4.0.4,
-4.1.1, and 4.1.2, are currently the _only_ versions known to succeed
-in building Emacs (as of v22.1).
+*** Building Emacs for Cygwin can fail with GCC 3
+
+As of Emacs 22.1, there have been stability problems with Cygwin
+builds of Emacs using GCC 3.  Cygwin users are advised to use GCC 4.
+
+*** Building the native MS-Windows port fails due to unresolved externals
+
+The linker error messages look like this:
+
+ oo-spd/i386/ctags.o:ctags.c:(.text+0x156e): undefined reference to `_imp__re_set_syntax'
+ collect2: ld returned 1 exit status
+
+This happens because GCC finds an incompatible header regex.h
+somewhere on the include path, before the version of regex.h supplied
+with Emacs.  One such incompatible version of regex.h is part of the
+GnuWin32 Regex package.
+
+The solution is to remove the incompatible regex.h from the include
+path, when compiling Emacs.  Alternatively, re-run the configure.bat
+script with the "-isystem C:/GnuWin32/include" switch (adapt for your
+system's place where you keep the GnuWin32 include files) -- this will
+cause the compiler to search headers in the directories specified by
+the Emacs Makefile _before_ it looks in the GnuWin32 include
+directories.
 
 *** Building the native MS-Windows port with Cygwin GCC can fail.