From 02581bf1f124029a1c0b20ce3c36cfcc4adc2616 Mon Sep 17 00:00:00 2001
From: Amar Takhar <verm@aegisub.org>
Date: Thu, 6 Aug 2009 04:35:35 +0000
Subject: [PATCH] Add a new option --enable-gcc-prec which will enable the use
 of gcc precompiled headers, this speeds up the build time (including one time
 builds) by several oders of magnitude. closes #975

Originally committed to SVN as r3369.
---
 aegisub/configure.in    | 10 ++++++++++
 aegisub/src/Makefile.am | 17 ++++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/aegisub/configure.in b/aegisub/configure.in
index 393ad689d..c483196c0 100644
--- a/aegisub/configure.in
+++ b/aegisub/configure.in
@@ -856,6 +856,16 @@ if test "$with_agi_cv_wxstc" = "no" || test "$enable_check_wx_stc:" = "yes"; the
 fi
 
 
+############################
+# Precompiled Header Support
+# Only works with gcc!
+############################
+
+AC_MSG_CHECKING([whether to use precompiled headers])
+AC_ARG_ENABLE(gcc-prec, [  --enable-gcc-prec          enable GCC precompiled headers (default=no)])
+AM_CONDITIONAL([PRECOMPILED_HEADER], [test "$enable_gcc_prec" = "yes"])
+
+
 ######################################################
 # Debugging support
 # This is added last so it doesn't slow down configure
diff --git a/aegisub/src/Makefile.am b/aegisub/src/Makefile.am
index 58cee4ae6..f6403dc02 100644
--- a/aegisub/src/Makefile.am
+++ b/aegisub/src/Makefile.am
@@ -1,6 +1,7 @@
 AUTOMAKE_OPTIONS = foreign
 SUFFIXES = .c .cpp .rc
 noinst_LIBRARIES= 
+AM_CXXFLAGS = 
 
 if BUILD_DARWIN
 libosxutil_subdir = libosxutil
@@ -8,12 +9,19 @@ libosxutil_lib = libosxutil/libosxutil.a
 libosxutil_ldflags = -framework CoreFoundation
 endif
 
+if PRECOMPILED_HEADER
+BUILT_SOURCES = stdwx.h.gch
+precompiled_header = stdwx.h
+AM_CXXFLAGS += -Winvalid-pch -fpch-deps -fpch-preprocess -include stdwx.h
+nodist_aegisub_2_2_SOURCES = stdwx.h.gch
+endif
+
 SUBDIRS = \
 	bitmaps \
 	libresrc \
 	$(libosxutil_subdir)
 
-AM_CXXFLAGS = -DAEGISUB -Iinclude -I../libffms/include @WX_CPPFLAGS@ @OPENMP_CXXFLAGS@ @LIBAVFORMAT_CFLAGS@ @LIBAVCODEC_CFLAGS@ @LIBSWSCALE_CFLAGS@ @LIBAVUTIL_CFLAGS@
+AM_CXXFLAGS += -DAEGISUB -Iinclude -I../libffms/include @WX_CPPFLAGS@ @OPENMP_CXXFLAGS@ @LIBAVFORMAT_CFLAGS@ @LIBAVCODEC_CFLAGS@ @LIBSWSCALE_CFLAGS@ @LIBAVUTIL_CFLAGS@
 
 bin_PROGRAMS = aegisub-2.2
 aegisub_2_2_LDADD = libresrc/libresrc.a $(libosxutil_lib)
@@ -21,6 +29,12 @@ aegisub_2_2_CPPFLAGS = @FREETYPE_CFLAGS@
 aegisub_2_2_LDFLAGS = @DEBUG_FLAGS@ @PROFILE_FLAGS@ @GL_LIBS@ @PTHREAD_LIBS@ @WX_LIBS@ @ICONV_LDFLAGS@ $(libosxutil_ldflags) @CCMALLOC_LDFLAGS@ @EFENCE_LDFLAGS@
 LIBS += @FREETYPE_LIBS@ @FONTCONFIG_LIBS@ @CCMALLOC_LIBS@
 
+if PRECOMPILED_HEADER
+# This doesn't depend on Makefile on purpose, you should already know what you're doing when using this.
+stdwx.h.gch: stdwx.h
+	@CXX@ -include ../acconf.h $(DEFAULT_INCLUDES) @CXXFLAGS@ $(AM_CXXFLAGS) @DEBUG_FLAGS@ @PROFILE_FLAGS@ stdwx.h
+endif
+
 if BUILD_DARWIN
 aegisub_2_2_LDFLAGS += -L/System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries
 endif
@@ -132,6 +146,7 @@ endif
 ## These aren't built, but are listed here so 'make dist' can always find all the sources
 ## This should also list all Win32 specific files
 EXTRA_aegisub_2_2_SOURCES = \
+	$(precompiled_header) \
 	font_file_lister.cpp \
 	$(FONT_LISTER) \
 	audio_player_dsound.cpp \