Always respect DEB_${flag}_{APPEND,SET} envvars.

Do that even when dpkg-buildpackage modifies environment variables. Also
document DEB_${flag}_{APPEND,SET} as recommended way to override standard build
flags.

1 files changed, 12 insertions, 0 deletions

diff --git a/dh b/dh
index aba8c270..5ea6643a 100755
--- a/dh
+++ b/dh
@@ -193,6 +193,18 @@ sequence addons like this:
 	%:
 		dh $@ --with quilt
 
+In order to override standard build flags, export appropriate environment
+variables as documented in the L<dpkg-buildflags(1)> manual page. They will be
+preferred over directly exported their counterparts (CFLAGS, CXXFLAGS, LDFLAGS
+etc.). For example, to append -Wall to the standard CFLAGS and CXXFLAGS, use:
+
+	#!/usr/bin/make -f
+	export DEB_CFLAGS_APPEND = -Wall
+	export DEB_CXXFLAGS_APPEND = -Wall
+	
+	%:
+		dh $@
+
 Here is an example of overriding where the B<dh_auto_>I<*> commands find
 the package's source, for a package where the source is located in a
 subdirectory.