pass user/maintainer provided CXXFLAGS to the Scintilla build process

 * Usually, Scintilla will now be built with -O2
 * this can improve performance significantly over the standard Scintilla -Os
   (up to 10%).
 * this also allows link-time-optimizing both Scintilla and SciTECO
   (which are linked statically) by adding -flto to CFLAGS, CXXFLAGS and LDFLAGS.
   Link-time-optimization will both reduce the total binary size
   and improve performance slightly since scintilla_send_message() can be
   inlined.
   An -O3 optimized Scintilla when linked with LTO results in an only 300kb
   larger SciTECO binary.
 * the highest possible optimization thus requires the following maintainer
   flags on the ./configure command line:
   CFLAGS="-O3 -mtune=native -march=native -flto"
   CXXFLAGS="-O3 -mtune=native -march=native -flto"
   LDFLAGS="-flto"
 * Windows and Debian builds use link-time-optimization now.
   On Windows - where we link in everything statically - building
   the dependant libraries with -flto could improve performance
   even more.
 * Debian builds respect the default hardening flags of the build
   server now. This should ensure that SciTECO is built for the
   correct architecture at the recommended optimization level etc.

1 files changed, 7 insertions, 1 deletions

diff --git a/debian/rules b/debian/rules
index c8bea8d..7d6302c 100755
--- a/debian/rules
+++ b/debian/rules
@@ -12,6 +12,11 @@
 # build dependencies.
 export TERM=
 
+# Build with link-time-optimizations
+export DEB_CFLAGS_MAINT_APPEND=-flto
+export DEB_CXXFLAGS_MAINT_APPEND=-flto
+export DEB_LDFLAGS_MAINT_APPEND=-flto
+
 %:
 	dh $@
 
@@ -19,7 +24,8 @@ build:
 	dh_testdir
 	dh_auto_configure -- \
 			  --enable-bootstrap \
-			  --with-interface=ncurses
+			  --with-interface=ncurses \
+	                  $(shell dpkg-buildflags --export=configure)
 	dh_auto_build
 	touch $@