X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=Makefile;h=e055b969c325ceb58afee6d27a0214cbf68f8bfd;hb=b4af7f773ef79c479cc25ee26063821220150a8a;hp=6798c6b4775de48c949240dff1b6ac9f061251d4;hpb=1200b6809dfd9d73bc4c7db76d288c35fa4b2ebe;p=deliverable%2Flinux.git

diff --git a/Makefile b/Makefile
index 6798c6b4775d..e055b969c325 100644
--- a/Makefile
+++ b/Makefile
@@ -993,7 +993,21 @@ prepare0: archprepare FORCE
 	$(Q)$(MAKE) $(build)=.
 
 # All the preparing..
-prepare: prepare0
+prepare: prepare0 prepare-objtool
+
+ifdef CONFIG_STACK_VALIDATION
+  has_libelf := $(shell echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf - &> /dev/null && echo 1 || echo 0)
+  ifeq ($(has_libelf),1)
+    objtool_target := tools/objtool FORCE
+  else
+    $(warning "Cannot use CONFIG_STACK_VALIDATION, please install libelf-dev or elfutils-libelf-devel")
+    SKIP_STACK_VALIDATION := 1
+    export SKIP_STACK_VALIDATION
+  endif
+endif
+
+PHONY += prepare-objtool
+prepare-objtool: $(objtool_target)
 
 # Generate some files
 # ---------------------------------------------------------------------------
@@ -1516,11 +1530,11 @@ image_name:
 # Clear a bunch of variables before executing the submake
 tools/: FORCE
 	$(Q)mkdir -p $(objtree)/tools
-	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(O) subdir=tools -C $(src)/tools/
+	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/
 
 tools/%: FORCE
 	$(Q)mkdir -p $(objtree)/tools
-	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(O) subdir=tools -C $(src)/tools/ $*
+	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(filter --j% -j,$(MAKEFLAGS))" O=$(shell cd $(objtree) && /bin/pwd) subdir=tools -C $(src)/tools/ $*
 
 # Single targets
 # ---------------------------------------------------------------------------