[vsipl++] Re: overriding autoconf's own exeext detection

[Ralf Wildenhues]

Hi Stefan,

* Stefan Seefeld wrote on Fri, Nov 11, 2005 at 06:08:29PM CET:
> Ralf Wildenhues wrote:
> 
> >Does the patch below fix it?
> 
> It looks good, though there is at least one more extension: '.inf',
> which is generated with optimization. Other files with extensions
> '.dbo', '.dla', etc. are created when object files are produces,
> but these don't seem to confuse configure.

I believe we do not need to add the other extensions (except for .inf)
to _AC_COMPILER_OBJEXT_REJECT, unless the compiler uses neither `.o' nor
`.obj' for object.  `configure' *should* in fact remove the other files
created during its tests.

> >Well, a shell pattern for exclusion is cheap, and the number of
> >different things to exclude seems not so high, so I think that's
> >the best solution for now.  Until one compiler produces an extension
> >that needs to be excluded for another one.
> 
> That's exactly my concern. As you can see above, the list of
> extensions to be excluded is growing...

I don't know a compiler that creates executables with these extensions
(but I haven't been around much in this regard).

OTOH, one of the most valuable assets of Autoconf is the number of very
experienced participants of its mailing list.  Let's just wait a few
days, someone may speak up if above assumptions are wrong.  :)

> Also, if I want to avoid upgrading autoconf, is there a way
> to fix the problem locally, say, in my aclocal.m4 file ?

Not that I know of.  You can always define your own macro, for example
a fixed version with the same name.  But that may be very fragile, not
compatible with the next or previous Autoconf, or anything, so I would
not recommend it.  Maybe AC_EXEEXT should offer a possibility to
override it.

Updated patch below.

Cheers,
Ralf

        * lib/autoconf/lang.m4 (_AC_COMPILER_OBJEXT_REJECT):
        Add `*.map' and `.inf' for Green Hills compiler.
        Reported by Stefan Seefeld <stefan at codesourcery.com>.

Index: lib/autoconf/lang.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/autoconf/lang.m4,v
retrieving revision 1.171
diff -u -r1.171 lang.m4
--- lib/autoconf/lang.m4	14 May 2005 07:00:40 -0000	1.171
+++ lib/autoconf/lang.m4	12 Nov 2005 14:11:15 -0000
@@ -421,6 +421,9 @@
 #
 # - *.xSYM
 #   Created on BeOS.  Seems to be per executable.
+# 
+# - *.map, *.inf
+#   Created by the Green Hills compiler.
 
 
 # _AC_COMPILER_OBJEXT_REJECT
@@ -428,7 +431,7 @@
 # Case/esac pattern matching the files to be ignored when looking for
 # compiled object files.
 m4_define([_AC_COMPILER_OBJEXT_REJECT],
-[*.$ac_ext | *.xcoff | *.tds | *.d | *.pdb | *.xSYM | *.bb | *.bbg])
+[*.$ac_ext | *.xcoff | *.tds | *.d | *.pdb | *.xSYM | *.bb | *.bbg | *.map | *.inf])
 
 
 # _AC_COMPILER_EXEEXT_REJECT