Hi Mats,
> The following appears with Gnulib pulled just minutes ago,
> when bootstrapping Inetutils on OpenIndiana. It was successful
> with Gnulib ba4b91abd from the 10th of January!
Thanks for the report. The patch below fixes it.
> The first change after my report was successful, but now
> you continue to push non-portable, or rather, seemingly
> version-dependent code.
No, the changes I pushed were neither non-portable nor version-dependent.
The cause of the failure is that inetutils/configure.ac invokes
AC_ISC_POSIX before AC_PROG_CC. But AC_ISC_POSIX is documented to expand
into an invocation of AC_SEARCH_LIBS; therefore it requires to run the C
compiler. It therefore does not really make sense to invoke AC_ISC_POSIX
before AC_PROG_CC. You were just lucky that it worked before.
This is a grey area of Autoconf: where you don't get a warning about wrong
order of invocation of two macros, and the result seemingly works, but
stops working when one of the involved macros changes a bit.
2020-01-18 Bruno Haible <br...@clisp.org>
Avoid error "m4_require: circular dependency of AC_LANG_COMPILER(C)".
Reported by Mats Erik Andersson <mats.anders...@gisladisker.se> in
<https://lists.gnu.org/archive/html/bug-gnulib/2020-01/msg00109.html>.
* m4/00gnulib.m4 (gl_COMPILER_CLANG): Use _AC_COMPILE_IFELSE, not
AC_EGREP_CPP.
diff --git a/m4/00gnulib.m4 b/m4/00gnulib.m4
index 36304b9..90e7e04 100644
--- a/m4/00gnulib.m4
+++ b/m4/00gnulib.m4
@@ -1,4 +1,4 @@
-# 00gnulib.m4 serial 6
+# 00gnulib.m4 serial 7
dnl Copyright (C) 2009-2020 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -58,13 +58,18 @@ AC_DEFUN([gl_COMPILER_CLANG],
dnl AC_REQUIRE([AC_PROG_CC])
AC_CACHE_CHECK([whether the compiler is clang],
[gl_cv_compiler_clang],
- [AC_EGREP_CPP([barfbarf],[
-#ifdef __clang__
-barfbarf
-#endif
- ],
- [gl_cv_compiler_clang=yes],
- [gl_cv_compiler_clang=no])
+ [dnl Use _AC_COMPILE_IFELSE instead of AC_EGREP_CPP, to avoid error
+ dnl "circular dependency of AC_LANG_COMPILER(C)" if AC_PROG_CC has
+ dnl not yet been invoked.
+ _AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM([[
+ #ifdef __clang__
+ barfbarf
+ #endif
+ ]],[[]])
+ ],
+ [gl_cv_compiler_clang=no],
+ [gl_cv_compiler_clang=yes])
])
])
AC_DEFUN([gl_COMPILER_PREPARE_CHECK_DECL],
