Hello.
On Wed, Oct 26, 2005 at 09:11:09PM +0200, Eli Zaretskii wrote:
> > the problem is this: ./configure runs
> > $CC -c -o conftst2.$ac_objext conftest.c
> > and then checks whether the compiler created conftst2.$ac_objext or
> > conftest$ac_objext
> >
> > If it were "conftest2.$ac_objext" instead, and someone run
> > bash ./configure
> > in a DJGPP environment, the check might not work.
>
> It _will_ work, even on 8+3 filesystems. [detailed explanation snipped]
No, the check doesn't _work_. It just _passes_ by shere good luck.
If $CC were not able to handle -c -o correctly, and created
conftest.$ac_objext instead of conftest2.$ac_objext, ./configure
would still think that $CC handles -c -o correctly.
I committed the patch attached to this mail.
Have a nice day,
Stepan Kasal
2005-10-27 Stepan Kasal <kasal@xxxxxx>
* lib/autoconf/c.m4 (AC_PROG_CC_C_O): "conftst2" -> "conftest2"
* lib/autoconf/fortran.m4 (_AC_PROG_FC_C_O): Likewise.
Index: lib/autoconf/c.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/autoconf/c.m4,v
retrieving revision 1.206
diff -u -r1.206 c.m4
--- lib/autoconf/c.m4 25 Oct 2005 07:55:31 -0000 1.206
+++ lib/autoconf/c.m4 27 Oct 2005 06:10:49 -0000
@@ -576,24 +576,25 @@
sed 's/[[^a-zA-Z0-9_]]/_/g;s/^[[0-9]]/_/'`
AC_CACHE_VAL(ac_cv_prog_cc_${ac_cc}_c_o,
[AC_LANG_CONFTEST([AC_LANG_PROGRAM([])])
-ac_clean_files_save=$ac_clean_files
-ac_clean_files="$ac_clean_files conftst2.*"
# Make sure it works both with $CC and with simple cc.
# We do the test twice because some compilers refuse to overwrite an
# existing .o file with -o, though they will create one.
-ac_try='$CC -c conftest.$ac_ext -o conftst2.$ac_objext >&AS_MESSAGE_LOG_FD'
-rm -f conftst2.*
+# (On an 8+3 filesystem, conftest2.* is not distinguishable from conftest.*,
+# thus the test always passes; but if the ./configure scripts are ever run
+# on good old DOS, it has to be with DJGPP, thus with gcc.)
+ac_try='$CC -c conftest.$ac_ext -o conftest2.$ac_objext >&AS_MESSAGE_LOG_FD'
+rm -f conftest2.*
if AC_TRY_EVAL(ac_try) &&
- test -f conftst2.$ac_objext && AC_TRY_EVAL(ac_try);
+ test -f conftest2.$ac_objext && AC_TRY_EVAL(ac_try);
then
eval ac_cv_prog_cc_${ac_cc}_c_o=yes
if test "x$CC" != xcc; then
# Test first that cc exists at all.
if AC_TRY_COMMAND(cc -c conftest.$ac_ext >&AS_MESSAGE_LOG_FD); then
- ac_try='cc -c conftest.$ac_ext -o conftst2.$ac_objext >&AS_MESSAGE_LOG_FD'
- rm -f conftst2.*
+ ac_try='cc -c conftest.$ac_ext -o conftest2.$ac_objext >&AS_MESSAGE_LOG_FD'
+ rm -f conftest2.*
if AC_TRY_EVAL(ac_try) &&
- test -f conftst2.$ac_objext && AC_TRY_EVAL(ac_try);
+ test -f conftest2.$ac_objext && AC_TRY_EVAL(ac_try);
then
# cc works too.
:
@@ -606,8 +607,7 @@
else
eval ac_cv_prog_cc_${ac_cc}_c_o=no
fi
-rm -f conftest* conftst2.*
-ac_clean_files=$ac_clean_files_save
+rm -f conftest*
])dnl
if eval "test \"`echo '$ac_cv_prog_cc_'${ac_cc}_c_o`\" = yes"; then
AC_MSG_RESULT([yes])
Index: lib/autoconf/fortran.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/autoconf/fortran.m4,v
retrieving revision 1.197
diff -u -r1.197 fortran.m4
--- lib/autoconf/fortran.m4 25 Oct 2005 07:55:31 -0000 1.197
+++ lib/autoconf/fortran.m4 27 Oct 2005 06:10:50 -0000
@@ -459,22 +459,18 @@
AC_CACHE_CHECK([whether $[]_AC_FC[] understands -c and -o together],
[ac_cv_prog_[]_AC_LANG_ABBREV[]_c_o],
[AC_LANG_CONFTEST([AC_LANG_PROGRAM([])])
-ac_clean_files_save=$ac_clean_files
-ac_clean_files="$ac_clean_files conftst2.*"
# We test twice because some compilers refuse to overwrite an existing
# `.o' file with `-o', although they will create one.
-ac_try='$[]_AC_FC[] $[]_AC_LANG_PREFIX[]FLAGS -c conftest.$ac_ext -o conftst2.$ac_objext >&AS_MESSAGE_LOG_FD'
-rm -f conftst2.*
+ac_try='$[]_AC_FC[] $[]_AC_LANG_PREFIX[]FLAGS -c conftest.$ac_ext -o conftest2.$ac_objext >&AS_MESSAGE_LOG_FD'
+rm -f conftest2.*
if AC_TRY_EVAL(ac_try) &&
- test -f conftst2.$ac_objext &&
+ test -f conftest2.$ac_objext &&
AC_TRY_EVAL(ac_try); then
ac_cv_prog_[]_AC_LANG_ABBREV[]_c_o=yes
else
ac_cv_prog_[]_AC_LANG_ABBREV[]_c_o=no
fi
-rm -f conftest* conftst2.*
-ac_clean_files=$ac_clean_files_save
-])
+rm -f conftest*])
if test $ac_cv_prog_[]_AC_LANG_ABBREV[]_c_o = no; then
AC_DEFINE([]_AC_FC[]_NO_MINUS_C_MINUS_O, 1,
[Define to 1 if your Fortran compiler doesn't accept
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