* Ralf Wildenhues wrote on Tue, May 23, 2006 at 11:05:53AM CEST:
> > * lib/autoconf/lang.m4 (_AC_COMPILER_EXEEXT_DEFAULT): Drop the
> > initialization of `ac_cv_exeext', do not override it if it was
> > already set. Add comment about this potential backward
> > incompatibility. Do not export `ac_cv_exeext', Libtool hasn't
> > needed this for years.
>
> Scratch this patch. It's Autoconf-2.13 that sets ac_cv_exeext=no.
Next try. OK to commit first the reversal patch posted in an earlier
message, then this one?
Cheers,
Ralf
2006-05-25 Stepan Kasal <[EMAIL PROTECTED]>
and Ralf Wildenhues <[EMAIL PROTECTED]>
* lib/autoconf/lang.m4 (_AC_COMPILER_EXEEXT_DEFAULT): Drop the
initialization of `ac_cv_exeext', do not override it if it was
already set, unless it was set to `no', for compatibility with
Autoconf-2.13, and comment this.
Do not export `ac_cv_exeext', Libtool hasn't needed this for years.
(_AC_COMPILER_EXEEXT_DEFAULT): Likewise, do not export it.
(_AC_COMPILER_EXEEXT_WORKS, _AC_COMPILER_EXEEXT_CROSS): Typos.
* doc/autoconf.texi (Compilers and Preprocessors) <EXEEXT>:
Document that this test may be overridden by setting
`ac_cv_exeext'.
--- lib/autoconf/lang.m4 2006-05-25 12:45:55.000000000 +0200
+++ lib/autoconf/lang.m4 2006-05-25 12:42:36.000000000 +0200
@@ -495,9 +495,11 @@
rm -f $ac_rmfiles
AS_IF([AC_TRY_EVAL(ac_link_default)],
-[# Be careful to initialize this variable, since it used to be cached.
-# Otherwise an old cache value of `no' led to `EXEEXT = no' in a Makefile.
-ac_cv_exeext=
+[# Autoconf-2.13 could set the ac_cv_exeext variable to `no'.
+# So ignore a value of `no', otherwise this would lead to `EXEEXT = no'
+# in a Makefile. Because we should not override ac_cv_exeext if it was
+# cached, so that the user can short-circuit this test for compilers
+# unknown to Autoconf.
for ac_file in $ac_files
do
test -f "$ac_file" || continue
@@ -509,16 +511,22 @@
# certainly right.
break;;
*.* )
- ac_cv_exeext=`expr "$ac_file" : ['[^.]*\(\..*\)']`
- # FIXME: I believe we export ac_cv_exeext for Libtool,
- # but it would be cool to find out if it's true. Does anybody
- # maintain Libtool? --akim.
- export ac_cv_exeext
+ if test "${ac_cv_exeext+set}" = set && test "$ac_cv_exeext" != no;
+ then :; else
+ ac_cv_exeext=`expr "$ac_file" : ['[^.]*\(\..*\)']`
+ fi
+ # We set ac_cv_exeext here because the later test for it is not
+ # safe: cross compilers may not add the suffix if given an `-o'
+ # argument, so we may need to know it at that point already.
+ # Even if this section looks crufty: it has the advantage of
+ # actually working.
break;;
* )
break;;
esac
-done],
+done
+test "$ac_cv_exeext" = no && ac_cv_exeext=
+],
[_AC_MSG_LOG_CONFTEST
AC_MSG_FAILURE([_AC_LANG compiler cannot create executables], 77)])
ac_exeext=$ac_cv_exeext
@@ -529,7 +537,7 @@
# _AC_COMPILER_EXEEXT_WORKS
# -------------------------
m4_define([_AC_COMPILER_EXEEXT_WORKS],
-[# Check the compiler produces executables we can run. If not, either
+[# Check that the compiler produces executables we can run. If not, either
# the compiler is broken, or we cross compile.
AC_MSG_CHECKING([whether the _AC_LANG compiler works])
# FIXME: These cross compiler hacks should be removed for Autoconf 3.0
@@ -553,7 +561,7 @@
# _AC_COMPILER_EXEEXT_CROSS
# -------------------------
m4_define([_AC_COMPILER_EXEEXT_CROSS],
-[# Check the compiler produces executables we can run. If not, either
+[# Check that the compiler produces executables we can run. If not, either
# the compiler is broken, or we cross compile.
AC_MSG_CHECKING([whether we are cross compiling])
AC_MSG_RESULT([$cross_compiling])
@@ -576,7 +584,6 @@
case $ac_file in
_AC_COMPILER_EXEEXT_REJECT ) ;;
*.* ) ac_cv_exeext=`expr "$ac_file" : ['[^.]*\(\..*\)']`
- export ac_cv_exeext
break;;
* ) break;;
esac
Index: doc/autoconf.texi
===================================================================
RCS file: /cvsroot/autoconf/autoconf/doc/autoconf.texi,v
retrieving revision 1.1023
diff -u -r1.1023 autoconf.texi
--- doc/autoconf.texi 25 May 2006 08:49:02 -0000 1.1023
+++ doc/autoconf.texi 25 May 2006 10:46:59 -0000
@@ -5911,7 +5911,9 @@
All the tests for compilers (@code{AC_PROG_CC}, @code{AC_PROG_CXX},
@code{AC_PROG_F77}) define the output variable @code{EXEEXT} based on
the output of the compiler, typically to the empty string if
-Posix and @samp{.exe} if a @acronym{DOS} variant.
+Posix and @samp{.exe} if a @acronym{DOS} variant. It can be overridden
+by passing the argument @[EMAIL PROTECTED] to
[EMAIL PROTECTED]
@ovindex OBJEXT
They also define the output variable @code{OBJEXT} based on the
