[Qemu-devel] [PATCH 02/30] Move generation of config-host.h to Makefile from configure

[Juan Quintela]

Use timestamp based appreach to avoid not needed recompilation.
Add it to rules.mak

Many thanks to Paolo Bonzini for helpding the design, and the debug.

Signed-off-by: Juan Quintela <address@hidden>
---
 Makefile      |   10 +++++++---
 configure     |   20 +-------------------
 create_config |    2 ++
 rules.mak     |    9 +++++++++
 4 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/Makefile b/Makefile
index e2ea91d..d7db158 100644
--- a/Makefile
+++ b/Makefile
@@ -24,7 +24,7 @@ else
 DOCS=
 endif

-build-all: $(TOOLS) $(DOCS) recurse-all
+build-all: config-host.h $(TOOLS) $(DOCS) recurse-all

 config-host.mak: configure
 ifneq ($(wildcard config-host.mak),)
@@ -32,10 +32,14 @@ ifneq ($(wildcard config-host.mak),)
        @sed -n "/.*Configured with/s/[^:]*: //p" $@ | sh
 endif

+%.c %.h: config-host.h
+config-host.h: config-host.h-timestamp
+config-host.h-timestamp: config-host.mak
+
 SUBDIR_MAKEFLAGS=$(if $(V),,--no-print-directory)
 SUBDIR_RULES=$(patsubst %,subdir-%, $(TARGET_DIRS))

-subdir-%:
+subdir-%: config-host.h
        $(call quiet-command,$(MAKE) $(SUBDIR_MAKEFLAGS) -C $* V="$(V)" 
TARGET_DIR="$*/" all,)

 $(filter %-softmmu,$(SUBDIR_RULES)): libqemu_common.a
@@ -191,7 +195,7 @@ clean:
         done

 distclean: clean
-       rm -f config-host.mak config-host.h config-host.ld $(DOCS) 
qemu-options.texi qemu-img-cmds.texi
+       rm -f config-host.mak config-host.h* config-host.ld $(DOCS) 
qemu-options.texi qemu-img-cmds.texi
        rm -f qemu-{doc,tech}.{info,aux,cp,dvi,fn,info,ky,log,pg,toc,tp,vr}
        for d in $(TARGET_DIRS) libhw32 libhw64; do \
        rm -rf $$d || exit 1 ; \
diff --git a/configure b/configure
index 99bf3e5..c2ccd8d 100755
--- a/configure
+++ b/configure
@@ -1522,13 +1522,8 @@ echo "-> Your SDL version is too old - please upgrade to 
have SDL support"
 fi

 config_host_mak="config-host.mak"
-config_host_h="config-host.h"
 config_host_ld="config-host.ld"

-#echo "Creating $config_host_mak and $config_host_h"
-
-test -f $config_host_h && mv $config_host_h ${config_host_h}~
-
 echo "# Automatically generated by configure - do not modify" > 
$config_host_mak
 printf "# Configured with:" >> $config_host_mak
 printf " '%s'" "$0" "$@" >> $config_host_mak
@@ -1765,18 +1760,6 @@ echo "LIBS+=$LIBS" >> $config_host_mak
 echo "LIBS_TOOLS+=$libs_tools" >> $config_host_mak
 echo "EXESUF=$EXESUF" >> $config_host_mak

-echo "/* Automatically generated by configure - do not modify */" > 
$config_host_h
-
-/bin/sh $source_path/create_config < $config_host_mak >> $config_host_h
-
-if test -f ${config_host_h}~ ; then
-  if cmp -s $config_host_h ${config_host_h}~ ; then
-    mv ${config_host_h}~ $config_host_h
-  else
-    rm ${config_host_h}~
-  fi
-fi
-
 # generate list of library paths for linker script

 $ld --verbose -v 2> /dev/null | grep SEARCH_DIR > ${config_host_ld}
@@ -2178,8 +2161,7 @@ fi
 echo "LDFLAGS+=$ldflags" >> $config_mak
 echo "QEMU_CFLAGS+=$cflags" >> $config_mak

-echo "/* Automatically generated by configure - do not modify */" > $config_h
-echo "#include \"../config-host.h\"" >> $config_h
+echo "#include \"../config-host.h\"" > $config_h

 /bin/sh $source_path/create_config < $config_mak >> $config_h

diff --git a/create_config b/create_config
index 5bc8fb6..30d0487 100755
--- a/create_config
+++ b/create_config
@@ -1,5 +1,7 @@
 #!/bin/sh

+echo "/* Automatically generated by create_config - do not modify */"
+
 while read line; do

 case $line in
diff --git a/rules.mak b/rules.mak
index c0315ac..3cbfa3d 100644
--- a/rules.mak
+++ b/rules.mak
@@ -23,3 +23,12 @@ quiet-command = $(if $(V),$1,$(if $(2),@echo $2 && $1, @$1))

 cc-option = $(shell if $(CC) $(1) $(2) -S -o /dev/null -xc /dev/null \
               > /dev/null 2>&1; then echo "$(2)"; else echo "$(3)"; fi ;)
+
+# Generate timestamp files for .h include files
+
+%.h: %.h-timestamp
+       @test -f $@ || cp $< $@
+
+%.h-timestamp: %.mak
+       $(call quiet-command, $(SRC_PATH)/create_config < $< > $@, "  GEN   
$*.h")
+       @cmp $@ $*.h >/dev/null 2>&1 || cp $@ $*.h
-- 
1.6.2.5