Cygwin patches

[Ken Brown <kbrown@cornell.edu>]

[-- Attachment #1: Type: text/plain, Size: 800 bytes --]

Now that you're preparing for emacs 23.2, could you please apply the 
cygwin patches that I submitted last June?

   http://lists.gnu.org/archive/html/emacs-devel/2009-06/msg00041.html
   http://lists.gnu.org/archive/html/emacs-devel/2009-06/msg00330.html

For your convenience, I've remade the patches against the current CVS 
source and attached them to this message.  I don't want to repeat the 
rationale for the patches that was already made in the threads cited 
above, but let me just add two comments:

1. The patches to browse-url.el and cygwin.h fix cygwin problems and 
should have no impact on other systems.

2. I built the official cygwin emacs-23.1 package with these patches, 
and there have been no reported problems after several months of use.

Thanks for your consideration.

Ken

[-- Attachment #2: browse-url.el.patch --]
[-- Type: text/plain, Size: 1389 bytes --]

--- origsrc/lisp/net/browse-url.el	2009-11-20 11:34:25.000000000 -0500
+++ src/lisp/net/browse-url.el	2009-11-20 11:35:28.000000000 -0500
@@ -693,7 +693,9 @@
 	  (cond ((not (buffer-modified-p)))
 		(browse-url-save-file (save-buffer))
 		(t (message "%s modified since last save" file))))))
-  (browse-url (browse-url-file-url file))
+  (if (eq system-type 'cygwin)
+      (shell-command (concat "cygstart " (shell-quote-argument file)))
+    (browse-url (browse-url-file-url file)))
   (run-hooks 'browse-url-of-file-hook))
 
 (defun browse-url-file-url (file)
@@ -830,11 +832,13 @@
 
 (defun browse-url-default-windows-browser (url &optional new-window)
   (interactive (browse-url-interactive-arg "URL: "))
-  (if (eq system-type 'ms-dos)
-      (if dos-windows-version
-	  (shell-command (concat "start " (shell-quote-argument url)))
-	(error "Browsing URLs is not supported on this system"))
-    (w32-shell-execute "open" url)))
+  (cond ((eq system-type 'ms-dos)
+	 (if dos-windows-version
+	     (shell-command (concat "start " (shell-quote-argument url)))
+	   (error "Browsing URLs is not supported on this system")))
+	((eq system-type 'cygwin)
+	 (shell-command (concat "cygstart " (shell-quote-argument url))))
+	(t (w32-shell-execute "open" url))))
 
 (defun browse-url-default-macosx-browser (url &optional new-window)
   (interactive (browse-url-interactive-arg "URL: "))

[-- Attachment #3: PROBLEMS.patch --]
[-- Type: text/plain, Size: 2993 bytes --]

--- origsrc/etc/PROBLEMS	2009-11-20 11:34:12.000000000 -0500
+++ src/etc/PROBLEMS	2009-11-20 11:34:46.000000000 -0500
@@ -255,6 +255,18 @@
 Cygwin malloc, the Cygwin memalign always returns ENOSYS.  A fix for this
 problem would be welcome.
 
+A workaround is to set G_SLICE=always-malloc before starting emacs.
+For example, in bash,
+
+  G_SLICE=always-malloc emacs
+
+or put
+
+  export G_SLICE=always-malloc
+
+in one of the bash startup files.  This  also has to be done before
+building emacs on Cygwin with Gtk+.
+
 * General runtime problems
 
 ** Lisp problems
@@ -2207,34 +2219,6 @@
 changes the keyboard layout depends on your Windows version; for XP,
 in the Languages tab, click "Details" and then "Key Settings".)
 
-** Cygwin build of Emacs hangs after rebasing Cygwin DLLs
-
-Usually, on Cygwin, one needs to rebase the DLLs if an application
-aborts with a message like this:
-
-  C:\cygwin\bin\python.exe: *** unable to remap C:\cygwin\bin\cygssl.dll to
-  same address as parent(0xDF0000) != 0xE00000
-
-However, since Cygwin DLL 1.5.17 was released, after such rebasing,
-Emacs hangs.
-
-This was reported to happen for Emacs 21.2 and also for the pretest of
-Emacs 22.1 on Cygwin.
-
-To work around this, build Emacs like this:
-
-  LDFLAGS='-Wl,--enable-auto-import -Wl,--enable-auto-image-base' ./configure
-  make LD='$(CC)'
-  make LD='$(CC)' install
-
-This produces an Emacs binary that is independent of rebasing.
-
-Note that you _must_ use LD='$(CC)' in the last two commands above, to
-prevent GCC from passing the "--image-base 0x20000000" option to the
-linker, which is what it does by default.  That option produces an
-Emacs binary with the base address 0x20000000, which will cause Emacs
-to hang after Cygwin DLLs are rebased.
-
 ** Interrupting Cygwin port of Bash from Emacs doesn't work.
 
 Cygwin 1.x builds of the ported Bash cannot be interrupted from the
@@ -2481,17 +2465,12 @@
 
 (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 the Cygwin port of emacs requires GCC 4
 
-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).
+As of Emacs 22.1, there have been problems with Cygwin builds of Emacs
+using GCC 3.  Cygwin users are advised to use GCC 4.  As far as we
+know, there have been no problems with Cygwin builds of Emacs using
+GCC 4.
 
 *** Building the native MS-Windows port with Cygwin GCC can fail.
 

[-- Attachment #4: cygwin.h.patch --]
[-- Type: text/plain, Size: 606 bytes --]

--- origsrc/src/s/cygwin.h	2009-06-21 00:38:20.000000000 -0400
+++ src/src/s/cygwin.h	2009-11-20 11:41:27.281250000 -0500
@@ -105,11 +105,7 @@
 #define SYSV_SYSTEM_DIR 1
 #define UNEXEC unexcw.o
 #define POSIX_SIGNALS 1
-/* force the emacs image to start high in memory, so dll relocation
-   can put things in low memory without causing all sorts of grief for
-   emacs lisp pointers */
-#define DATA_SEG_BITS 0x20000000
-#define LINKER $(CC) -Wl,--image-base,DATA_SEG_BITS
+#define LINKER $(CC)
 
 /* Use terminfo instead of termcap.  Fewer environment variables to
    go wrong, more terminal types. */