next-error fails to find file on Cygwin with recursive make

next-error fails to find file on Cygwin with recursive make

[Gareth Rees]

I am using

GNU Emacs 22.1.1 (i386-mingw-nt5.1.2600) of 2007-06-02 on RELEASE
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4) --cflags -Ic:/gnuwin32/include'

I have `shell-file-name' set to "bash" and I type M-x compile RET make RET.

Cygwin's "make" produces the following output in the *compilation* buffer:

----------------------------------------------------------------------------
-*- mode: compilation; default-directory: "c:/tmp/test/" -*-
Compilation started at Fri Apr 25 13:13:20

make
make -f src/Makefile
make[1]: Entering directory `/cygdrive/c/tmp/test'
gcc -Wall -g -o build/test.o -c src/test.c
src/test.c:1:2: #error Error
make[1]: *** [build/test.o] Error 1
make[1]: Leaving directory `/cygdrive/c/tmp/test'
make: *** [all] Error 2

Compilation exited abnormally with code 2 at Fri Apr 25 13:13:21
----------------------------------------------------------------------------

Now I type M-x next-error RET. I expect Emacs to go to the location of 
the first error, but instead it asks me thiis question:

    Find this error in (default src/test.c): c:/cygdrive/c/tmp/test

The reason it can't find the file is that 
`compilation-directory-matcher' has matched the recursive make's 
"Entering directory" line, which contains an absolute path name in 
Cygwin syntax; and then `compilation-find-file' has called 
`expand-file-name', which has converted `/cygdrive/c/tmp/test' into the 
incorrect `c:/cygdrive/c/tmp/test' instead of the correct `c:/tmp/test'.

I am aware that I can work around this problem by advising 
`expand-file-name' to recognize Cygwin path names and convert them to 
path names that Emacs recognizes, for example like this:

(defadvice expand-file-name (before cygpath-convert-to-emacs-path activate)
  (let ((name (ad-get-arg 0)))
    (when (string-match "^/cygdrive/\\([a-z]\\)\\(/.*\\)" name)
      (ad-set-arg 0 (concat (match-string 1 name) ":" (match-string 2 
name))))))

However, it would be nice if recursive make in Cygwin worked in Emacs 
out of the box.

-- 
Gareth Rees

Re: next-error fails to find file on Cygwin with recursive make

[Stefan Monnier]

> Now I type M-x next-error RET. I expect Emacs to go to the location of the
> first error, but instead it asks me thiis question:

>    Find this error in (default src/test.c): c:/cygdrive/c/tmp/test

You probably want to use cygwin-mount.el.  I always thought it would be
a nice addition to Emacs, but people more knowledgeable about Windows
seemed to be rather opposed to it last time this popped up.


        Stefan

Re: next-error fails to find file on Cygwin with recursive make

[Eli Zaretskii]

> Date: Fri, 25 Apr 2008 13:52:10 +0100
> From: Gareth Rees <gareth.rees@pobox.com>
> Cc: Gareth Rees <gareth.rees@pobox.com>
> 
>     Find this error in (default src/test.c): c:/cygdrive/c/tmp/test
> 
> The reason it can't find the file is that 
> `compilation-directory-matcher' has matched the recursive make's 
> "Entering directory" line, which contains an absolute path name in 
> Cygwin syntax; and then `compilation-find-file' has called 
> `expand-file-name', which has converted `/cygdrive/c/tmp/test' into the 
> incorrect `c:/cygdrive/c/tmp/test' instead of the correct `c:/tmp/test'.
> 
> I am aware that I can work around this problem by advising 
> `expand-file-name' to recognize Cygwin path names and convert them to 
> path names that Emacs recognizes, for example like this:
> 
> (defadvice expand-file-name (before cygpath-convert-to-emacs-path activate)
>   (let ((name (ad-get-arg 0)))
>     (when (string-match "^/cygdrive/\\([a-z]\\)\\(/.*\\)" name)
>       (ad-set-arg 0 (concat (match-string 1 name) ":" (match-string 2 
> name))))))
> 
> However, it would be nice if recursive make in Cygwin worked in Emacs 
> out of the box.

It does, if you use the Cygwin build of Emacs.

RE: next-error fails to find file on Cygwin with recursive make

[Drew Adams]

> > Now I type M-x next-error RET. I expect Emacs to go to the 
> > location of the first error, but instead it asks me thiis question:
> 
> >    Find this error in (default src/test.c): c:/cygdrive/c/tmp/test
> 
> You probably want to use cygwin-mount.el.  I always thought 
> it would be
> a nice addition to Emacs, but people more knowledgeable about Windows
> seemed to be rather opposed to it last time this popped up.

FWIW - I'm not knowledgeable about Windows, but I use Windows, and I too think
it should be added to Emacs. Or at least made more obvious to Windows users.

Re: next-error fails to find file on Cygwin with recursive make

[Gareth Rees]

Stefan Monnier wrote:
>> Now I type M-x next-error RET. I expect Emacs to go to the  
>> location of the
>> first error, but instead it asks me thiis question:
>>
>>    Find this error in (default src/test.c): c:/cygdrive/c/tmp/test
>
> You probably want to use cygwin-mount.el.

That's very helpful, thank you.

(And now I've learned about `file-name-handler-alist' too.)

-- 
Gareth Rees