# Patch to make the build system honour CC, CXX, CFLAGS, CXXFLAGS and LDFLAGS. 
# See http://subversion.ffado.org/ticket/382 for more information.
# Applied upstream.

Index: SConstruct
===================================================================
--- SConstruct	(revision 2575)
+++ SConstruct	(revision 2577)
@@ -77,7 +77,8 @@
     EnumVariable('DIST_TARGET', 'Build target for cross compiling packagers', 'auto', allowed_values=('auto', 'i386', 'i686', 'x86_64', 'powerpc', 'powerpc64', 'none' ), ignorecase=2),
     BoolVariable( "ENABLE_OPTIMIZATIONS", "Enable optimizations and the use of processor specific extentions (MMX/SSE/...).", False ),
     BoolVariable( "PEDANTIC", "Enable -Werror and more pedantic options during compile.", False ),
-    ( "COMPILE_FLAGS", "Add additional flags to the environment.\nOnly meant for distributors and gentoo-users who want to over-optimize their built.\n Using this is not supported by the ffado-devs!" ),
+    BoolVariable( "CUSTOM_ENV", "Respect CC, CXX, CFLAGS, CXXFLAGS and LDFLAGS.\nOnly meant for distributors and gentoo-users who want to over-optimize their build.\n Using this is not supported by the ffado-devs!", False ),
+    ( "COMPILE_FLAGS", "Deprecated (use CFLAGS and CXXFLAGS with CUSTOM_ENV=True instead).  Add additional flags to the environment.\nOnly meant for distributors and gentoo-users who want to over-optimize their build.\n Using this is not supported by the ffado-devs!" ),
     EnumVariable( "ENABLE_SETBUFFERSIZE_API_VER", "Report API version at runtime which includes support for dynamic buffer resizing (requires recent jack).", 'auto', allowed_values=('auto', 'true', 'false', 'force'), ignorecase=2),
 
     )
@@ -87,14 +88,42 @@
 
 env = Environment( tools=['default','scanreplace','pyuic','pyuic4','dbus','doxygen','pkgconfig'], toolpath=['admin'], ENV = buildenv, options=opts )
 
+custom_flags = False
+
 if env.has_key('COMPILE_FLAGS') and len(env['COMPILE_FLAGS']) > 0:
+    print "The COMPILE_FLAGS option is deprecated. Use CFLAGS and CXXFLAGS with CUSTOM_ENV=True instead"
+    custom_flags = True
+    env.MergeFlags(env['COMPILE_FLAGS'])
+
+if env['CUSTOM_ENV']:
+    custom_flags = True
+
+    # Honour the user choice of compiler (if any).
+    if os.environ.has_key('CC') and len(os.environ['CC']) > 0:
+        env['CC'] = os.environ['CC']
+    if os.environ.has_key('CXX') and len(os.environ['CXX']) > 0:
+        env['CXX'] = os.environ['CXX']
+
+    # Honour the user supplied flags (if any), but notify the user that this is not supported.
+    if os.environ.has_key('CFLAGS') and len(os.environ['CFLAGS']) > 0:
+        env.Append(CFLAGS = str(os.environ['CFLAGS'].replace('\"', '')))
+    if os.environ.has_key('CXXFLAGS') and len(os.environ['CXXFLAGS']) > 0:
+        env.Append(CXXFLAGS = str(os.environ['CXXFLAGS'].replace('\"', '')))
+    if os.environ.has_key('LDFLAGS') and len(os.environ['LDFLAGS']) > 0:
+        env.Append(LINKFLAGS = str(os.environ['LDFLAGS'].replace('\"', '')))
+
+if custom_flags:
     print '''
  * Usage of additional flags is not supported by the ffado-devs.
  * Use at own risk!
  *
- * Currentl value is '%s'
- ''' % env['COMPILE_FLAGS']
-    env.MergeFlags(env['COMPILE_FLAGS'])
+ * Flags in use:
+ *   CC = %s
+ *   CXX = %s
+ *   CFLAGS = %s
+ *   CXXFLAGS = %s
+ *   LDFLAGS = %s
+''' % (env['CC'], env['CXX'], env['CFLAGS'], env['CXXFLAGS'], env['LINKFLAGS'])
 
 Help( """
 For building ffado you can set different options as listed below. You have to
@@ -331,7 +360,7 @@
         oldcf = env['CFLAGS']
     else:
         oldcf = ""
-    oldcf = env.Append(CFLAGS = '-std=c99')
+    env.Append(CFLAGS = '-std=c99')
     if conf.CheckLibWithHeader( "m", "math.h", "c", "lrint(3.2);" ):
         HAVE_LRINT = 1
     else:
@@ -415,7 +444,8 @@
     print "Doing a debug build"
     env.MergeFlags( "-Wall -g -DDEBUG" )
     env['DEBUG_MESSAGES'] = True
-else:
+elif not custom_flags:
+    # Only merge -O2 to flags if the user has not specified custom flags.
     env.MergeFlags( "-O2" )
 
 if env['DEBUG_MESSAGES']: