Fix coreboot makefiles not to produce half baked output.

There were cases where output file was generated and modified within
a recipe. If make was interrupted, it could exit with an output file
that appears as up-to-date, but was generated with incomplete recipe.

The output file should be created only when successful, in an atomic
operation. There could be other places in the make system which
require a similar fix, this needs to be investigated further.

Change-Id: I25c8ee23577a460eace196fd28c23cc67aa72a9a
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/830
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

diff --git a/src/arch/x86/Makefile.inc b/src/arch/x86/Makefile.inc
index 0a97ee57168ae92f48ec0f8d3d8b7e13b0b91a0e..5917ce50a4a4c26f8cc50e910fd790fb74867cf4 100755 (executable)
--- a/src/arch/x86/Makefile.inc
+++ b/src/arch/x86/Makefile.inc
@@ -146,11 +146,12 @@ $(objutil)/options/build_opt_tbl: $(top)/util/options/build_opt_tbl.c $(top)/src
 
 $(obj)/coreboot_ram: $(obj)/coreboot_ram.o $(src)/arch/x86/coreboot_ram.ld #ldoptions
        @printf "    CC         $(subst $(obj)/,,$(@))\n"
-       $(CC) -nostdlib -nostartfiles -static -o $@ -L$(obj) -T $(src)/arch/x86/coreboot_ram.ld $(obj)/coreboot_ram.o
-       $(NM) -n $(obj)/coreboot_ram | sort > $(obj)/coreboot_ram.map
-       $(OBJCOPY) --only-keep-debug $@ $(obj)/coreboot_ram.debug
-       $(OBJCOPY) --strip-debug $@
-       $(OBJCOPY) --add-gnu-debuglink=$(obj)/coreboot_ram.debug $@
+       $(CC) -nostdlib -nostartfiles -static -o $@.tmp -L$(obj) -T $(src)/arch/x86/coreboot_ram.ld $(obj)/coreboot_ram.o
+       $(NM) -n $@.tmp | sort > $@.map
+       $(OBJCOPY) --only-keep-debug $@.tmp $@.debug
+       $(OBJCOPY) --strip-debug $@.tmp
+       $(OBJCOPY) --add-gnu-debuglink=$@.debug $@.tmp
+       mv $@.tmp $@
 
 $(obj)/coreboot_ram.o: $(obj)/arch/x86/lib/c_start.ramstage.o $$(driver-objs) $(obj)/coreboot.a $(LIBGCC_FILE_NAME)
        @printf "    CC         $(subst $(obj)/,,$(@))\n"
@@ -168,12 +169,12 @@ ifeq ($(CONFIG_AP_CODE_IN_CAR),y)
 
 $(obj)/coreboot_ap: $(obj)/mainboard/$(MAINBOARDDIR)/ap_romstage.o
        @printf "    CC         $(subst $(obj)/,,$(@))\n"
-       $(CC) -nostdlib -nostartfiles -static -o $@ -L$(obj) -T $(src)/arch/x86/init/ldscript_apc.lb $^
-       $(OBJCOPY) --only-keep-debug $@ $(obj)/coreboot_ap.debug
-       $(OBJCOPY) --strip-debug $@
-       $(OBJCOPY) --add-gnu-debuglink=$(obj)/coreboot_ap.debug $@
-       $(NM) -n $(obj)/coreboot_ap | sort > $(obj)/coreboot_ap.map
-
+       $(CC) -nostdlib -nostartfiles -static -o $@.tmp -L$(obj) -T $(src)/arch/x86/init/ldscript_apc.lb $^
+       $(OBJCOPY) --only-keep-debug $@.tmp $@.debug
+       $(OBJCOPY) --strip-debug $@.tmp
+       $(OBJCOPY) --add-gnu-debuglink=$@.debug $@.tmp
+       $(NM) -n $@.tmp | sort > $@.map
+       mv $@.tmp $@
 
 endif
 
@@ -334,11 +335,12 @@ $(obj)/mainboard/$(MAINBOARDDIR)/bootblock.inc: $(src)/arch/x86/init/$(subst ",,
 
 $(obj)/bootblock.elf: $(obj)/mainboard/$(MAINBOARDDIR)/bootblock.o $(obj)/bootblock/ldscript.ld
        @printf "    LINK       $(subst $(obj)/,,$(@))\n"
-       $(CC) -nostdlib -nostartfiles -static -o $@ -L$(obj) -T $(obj)/bootblock/ldscript.ld $<
-       $(NM) -n $(obj)/bootblock.elf | sort > $(obj)/bootblock.map
-       $(OBJCOPY) --only-keep-debug $@ $(obj)/bootblock.debug
-       $(OBJCOPY) --strip-debug $@
-       $(OBJCOPY) --add-gnu-debuglink=$(obj)/bootblock.debug $@
+       $(CC) -nostdlib -nostartfiles -static -o $@.tmp -L$(obj) -T $(obj)/bootblock/ldscript.ld $<
+       $(NM) -n $@.tmp | sort > $(obj)/bootblock.map
+       $(OBJCOPY) --only-keep-debug $@.tmp $(obj)/bootblock.debug
+       $(OBJCOPY) --strip-debug $@.tmp
+       $(OBJCOPY) --add-gnu-debuglink=$(obj)/bootblock.debug $@.tmp
+       mv $@.tmp $@
 
 #######################################################################
 # Build the romstage