From c7c3144f1f6f56bb4a20050b939e2a1da26f98cc Mon Sep 17 00:00:00 2001
From: Petter Urkedal <paurkedal@gmail.com>
Date: Sun, 14 Aug 2011 12:57:27 +0200
Subject: [PATCH] Use pkg-config to pick up libatomic_ops, etc.

* configure.ac: Remove checks for ar and ranlib.
* configure.ac: Replace AC_CHECK_HEADER with PKG_CHECK_MODULES when
checking for libatomic_ops.  The macro sets the appropriate flags, so
simplify accordingly.
* Makefile.am, configure.ac: Set ATOMIC_OPS_CFLAGS in configure.ac
instead of conditionally doing it in Makefile.am, to be more consistent
with the pkg-config case.
* configure.ac: Fix a typo and some phrases.
---
 Makefile.am  |  8 +++-----
 configure.ac | 20 +++++++++-----------
 2 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index f389e3a3..6dd29808 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -33,11 +33,9 @@
 SUBDIRS =
 
 ACLOCAL_AMFLAGS = -I m4
-AM_CPPFLAGS = -I$(top_builddir)/include -I$(top_srcdir)/include
-if USE_INTERNAL_LIBATOMIC_OPS
-AM_CPPFLAGS += -I$(top_builddir)/libatomic_ops/src \
-	       -I$(top_srcdir)/libatomic_ops/src
-endif
+AM_CPPFLAGS = \
+	-I$(top_builddir)/include -I$(top_srcdir)/include \
+	$(ATOMIC_OPS_CFLAGS)
 
 # Initialize variables so that we can declare files locally.
 EXTRA_DIST =
diff --git a/configure.ac b/configure.ac
index 82da25fe..b6c60efd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -36,9 +36,6 @@ AM_PROG_CC_C_O
 AC_PROG_CXX
 
 AM_PROG_AS
-## FIXME: really needed? (AC_LIBTOOL already provides this)
-AC_CHECK_TOOL(AR, ar)
-AC_CHECK_TOOL(RANLIB, ranlib, :)  # :)
 
 AC_PROG_INSTALL
 
@@ -692,29 +689,30 @@ AM_CONDITIONAL(USE_LIBDIR, test -z "$with_cross_host")
 # found.
 AC_ARG_WITH([libatomic-ops],
     [AS_HELP_STRING([--with-libatomic-ops[=yes|no|check]],
-                    [Use a pre-installed libatomic_ops? (default: check)])],
+                    [Use a external libatomic_ops? (default: check)])],
     [], [with_libatomic_ops=check])
 
 # Check for an external libatomic_ops if the answer was yes or check.  If not
 # found, fail on yes, and convert check to no.
 AS_IF([test x"$with_libatomic_ops" != xno],
-  [ AC_CHECK_HEADER([atomic_ops.h], [],
+  [ PKG_CHECK_MODULES([ATOMIC_OPS], [atomic_ops], [],
       [ AS_IF([test x"$with_libatomic_ops" != xcheck],
-              [AC_MSG_ERROR([A pre-installed libatomic_ops was not found.])])
+              [AC_MSG_ERROR([A external libatomic_ops was not found.])])
         with_libatomic_ops=no ]) ])
 
 # If we have neither an external or an internal version, offer a useful hint
 # and exit.
 AS_IF([test x"$with_libatomic_ops" = xno -a ! -e "$srcdir/libatomic_ops"],
-  [ AC_MSG_ERROR([libatomic_ops is required.  You can either install it on your system, or fetch and unpack a resent version into the source directory and link or rename it to libatomic_ops.]) ])
+  [ AC_MSG_ERROR([libatomic_ops is required.  You can either install it on your system, or fetch and unpack a recent version into the source directory and link or rename it to libatomic_ops.]) ])
 
-# Finally, emit the definitions for bundled or pre-installed AO.
+# Finally, emit the definitions for bundled or external AO.
 AC_MSG_CHECKING([which libatomic_ops to use])
 AS_IF([test x"$with_libatomic_ops" != xno],
-  [ AC_MSG_RESULT([pre-installed])
-    ATOMIC_OPS_LIBS="-latomic_ops"
-    AC_SUBST([ATOMIC_OPS_LIBS]) ],
+  [ AC_MSG_RESULT([external]) ],
   [ AC_MSG_RESULT([internal])
+    ATOMIC_OPS_CFLAGS='-I$(top_builddir)/libatomic_ops/src -I$(top_srcdir)/libatomic_ops/src'
+    ATOMIC_OPS_LIBS=""
+    AC_SUBST([ATOMIC_OPS_CFLAGS])
     AC_CONFIG_SUBDIRS([libatomic_ops])
   ])
 AM_CONDITIONAL([USE_INTERNAL_LIBATOMIC_OPS],
-- 
2.40.0