Thanks for the report, it's a known bug. In fact this bug is not new,
what is new is that the core machinery now correctly catches it.
The problem is related to the fact that AC_PROG_CC can be expanded
twice, and since the first expansion expands AC_PROG_CPP, the second
expansion of AC_PROG_CC will complain because AC_PROG_CPP was run
beforehand.
The following patch fixes this issue. There was another obvious
implementation possibility: having AC_LANG_COMPILER(C) provide
AC_PROG_CC, but I think this approach is better.
Index: ChangeLog
from Akim Demaille <[EMAIL PROTECTED]>
When running
AC_INIT
AC_PROG_CC
AC_LANG_COMPILER_REQUIRE
AC_PROG_CC is expanded twice, because AC_PROG_CC provides
`AC_PROG_CC', and not `AC_LANG_COMPILER(C)' as expected by
AC_LANG_COMPILER_REQUIRE.
* aclang.m4 (AC_LANG_COMPILER(C)): Instead of calling AC_PROG_CC,
require it.
(AC_LANG_COMPILER(C++), AC_LANG_COMPILER(Fortran 77)): Likewise.
Index: aclang.m4
===================================================================
RCS file: /cvs/autoconf/aclang.m4,v
retrieving revision 1.81
diff -u -u -r1.81 aclang.m4
--- aclang.m4 2000/11/03 14:01:58 1.81
+++ aclang.m4 2000/11/07 10:09:44
@@ -675,7 +675,7 @@
# -------------------
# Find the C compiler. Must be AC_DEFUN'd to be AC_REQUIRE'able.
AC_DEFUN([AC_LANG_COMPILER(C)],
-[AC_PROG_CC])
+[AC_REQUIRE([AC_PROG_CC])])
# ac_cv_prog_gcc
@@ -869,7 +869,7 @@
# ---------------------
# Find the C++ compiler. Must be AC_DEFUN'd to be AC_REQUIRE'able.
AC_DEFUN([AC_LANG_COMPILER(C++)],
-[AC_PROG_CXX])
+[AC_REQUIRE([AC_PROG_CXX])])
# ac_cv_prog_gxx
@@ -951,7 +951,7 @@
# Find the Fortran 77 compiler. Must be AC_DEFUN'd to be
# AC_REQUIRE'able.
AC_DEFUN([AC_LANG_COMPILER(Fortran 77)],
-[AC_PROG_F77])
+[AC_REQUIRE([AC_PROG_F77])])
# ac_cv_prog_g77
