[tip:core/objtool] tools: Support relative directory path for 'O='

[tip-bot for Josh Poimboeuf]

Commit-ID:  e17cf3a80d4ba0c4e40bf1a89deb1354c2e10e14
Gitweb:     http://git.kernel.org/tip/e17cf3a80d4ba0c4e40bf1a89deb1354c2e10e14
Author:     Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
AuthorDate: Thu, 3 Mar 2016 08:53:43 -0600
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 3 Mar 2016 16:13:00 +0100

tools: Support relative directory path for 'O='

Running "make O=foo" (with a relative directory path) fails with:

  scripts/Makefile.include:3: *** O=foo does not exist.  Stop.
  /home/jpoimboe/git/linux/Makefile:1547: recipe for target 'tools/objtool' failed

The tools Makefile gets confused by the relative path and tries to build
objtool in tools/foo.  Convert the output directory to an absolute path
before passing it to the tools Makefile.

Reported-by: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-next@xxxxxxxxxxxxxxx
Cc: linux@xxxxxxxxxxxx
Cc: live-patching@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/94a078c6c998fac9f01a14f574008bf7dff40191.1457016803.git.jpoimboe@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 62be03b..2c27a01 100644
--- a/Makefile
+++ b/Makefile
@@ -1509,11 +1509,11 @@ 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
 # ---------------------------------------------------------------------------