build: use AX_IS_RELEASE() and AX_COMPILER_FLAGS()

The autoconf macros AX_COMPILER_FLAGS_{CFLAGS|GIR|LDFLAGS} test
for compiler and linker support of various flags, and add the flags to
the generated output.

If the command-line option '--enable-compile-warnings' is specified to
'configure', a number of additional warning options is also added to the
output. This is the default.

This update requires the presence of the GNU autoconf-archive in the
system.

1 files changed, 30 insertions, 2 deletions

diff --git a/configure.ac b/configure.ac
index 5e56dfd2..57495032 100644
--- a/configure.ac
+++ b/configure.ac
@@ -51,6 +51,33 @@ LT_PREREQ([2.2])
 LT_INIT([disable-static])
 
 dnl-----------------------------------------------------------------------------
+dnl Compiler warnings
+dnl
+
+dnl Make sure autoconf-archive is available
+m4_pattern_forbid([^AX_(COMPILER_FLAGS|COMPILER_FLAGS_(CFLAGS|GIR|LDFLAGS))\b],
+  [Unexpanded AX_ macro found. Please install GNU autoconf-archive])
+
+dnl Detect git or release builds
+AX_IS_RELEASE([git-directory])
+
+dnl Function type cast disabled: used throughout the code especially to
+dnl cast GAsyncReadyCallbacks with the real object type instead of GObject
+DISABLED_WARNINGS="${DISABLED_WARNINGS} -Wno-cast-function-type"
+
+dnl All message protocol structs are packed, never complain about it
+DISABLED_WARNINGS="${DISABLED_WARNINGS} -Wno-packed"
+
+dnl Setup compiler checks
+AX_COMPILER_FLAGS()
+AX_COMPILER_FLAGS_CFLAGS(,,,[${DISABLED_WARNINGS}])
+
+dnl Specify gnu89 mode
+if test "$GCC" = "yes"; then
+   CFLAGS="$CFLAGS -std=gnu89"
+fi
+
+dnl-----------------------------------------------------------------------------
 dnl Version definitions
 dnl
 
@@ -384,8 +411,6 @@ case $with_qmi in
         ;;
 esac
 
-NM_COMPILER_WARNINGS
-
 dnl-----------------------------------------------------------------------------
 dnl Distribution version string
 dnl
@@ -534,7 +559,10 @@ echo "
       compiler:                ${CC}
       cflags:                  ${CFLAGS}
       ldflags:                 ${LDFLAGS}
+      warn cflags:             ${WARN_CFLAGS}
+      warn ldflags:            ${WARN_LDFLAGS}
       maintainer mode:         ${USE_MAINTAINER_MODE}
+      release:                 ${ax_is_release}
 
     System paths:
       prefix:                  ${prefix}