[PATCH libXaw] config: add AM_PROG_CC_C_O for per-target compilation flags

[Gaetan Nadon]

Per-target compilation flags (libXaw7_la_CFLAGS) are required
when multiple targets which require different compiler flags,
are build in the same makefile.

Automake issues a command with -c and -o flags which not all compilers
support. The object fles are prefixed with libXaw7_la.
The macro AM_PROG_CC_C_O must then be used to provide this feature
on compilers that do not have it. If not, a warning is issued at make time.

This macros checks for compiler support and if missing, uses a "compile"
script it generates in the package root directory.

Signed-off-by: Gaetan Nadon <memsize at videotron.ca>
---
 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/configure.ac b/configure.ac
index de010a3..ee370dc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -21,6 +21,7 @@ AC_PROG_CC
 AC_PROG_LIBTOOL
 AC_PROG_AWK
 AC_PROG_SED
+AM_PROG_CC_C_O
 
 # Need to call this explicitly since the first call to PKG_CHECK_MODULES
 # is in an if statement, and later calls would break if it's skipped.
-- 
1.6.0.4