[tip:perf/core] tools: Set the maximum optimization level according to the compiler being used

[tip-bot for Arnaldo Carvalho de Melo]

Commit-ID:  49b3cd306e60b9d889c775cb2ebb709f80dd8ae9
Gitweb:     http://git.kernel.org/tip/49b3cd306e60b9d889c775cb2ebb709f80dd8ae9
Author:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Tue, 14 Feb 2017 10:55:27 -0300
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Tue, 14 Feb 2017 10:55:27 -0300

tools: Set the maximum optimization level according to the compiler being used

To avoid this when using clang:

  warning: optimization level '-O6' is not supported; using '-O3' instead

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-kaghp8ddvzdsg03putemcq96@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/lib/api/Makefile     | 8 +++++++-
 tools/lib/subcmd/Makefile  | 8 +++++++-
 tools/perf/Makefile.config | 4 ++++
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/tools/lib/api/Makefile b/tools/lib/api/Makefile
index adba83b..eb6e0b3 100644
--- a/tools/lib/api/Makefile
+++ b/tools/lib/api/Makefile
@@ -17,7 +17,13 @@ MAKEFLAGS += --no-print-directory
 LIBFILE = $(OUTPUT)libapi.a
 
 CFLAGS := $(EXTRA_WARNINGS) $(EXTRA_CFLAGS)
-CFLAGS += -ggdb3 -Wall -Wextra -std=gnu99 -O6 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fPIC
+CFLAGS += -ggdb3 -Wall -Wextra -std=gnu99 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fPIC
+
+ifeq ($(CC), clang)
+  CFLAGS += -O3
+else
+  CFLAGS += -O6
+endif
 
 # Treat warnings as errors unless directed not to
 ifneq ($(WERROR),0)
diff --git a/tools/lib/subcmd/Makefile b/tools/lib/subcmd/Makefile
index 3f8cc44..3d1c3b5 100644
--- a/tools/lib/subcmd/Makefile
+++ b/tools/lib/subcmd/Makefile
@@ -19,7 +19,13 @@ MAKEFLAGS += --no-print-directory
 LIBFILE = $(OUTPUT)libsubcmd.a
 
 CFLAGS := $(EXTRA_WARNINGS) $(EXTRA_CFLAGS)
-CFLAGS += -ggdb3 -Wall -Wextra -std=gnu99 -O6 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fPIC
+CFLAGS += -ggdb3 -Wall -Wextra -std=gnu99 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fPIC
+
+ifeq ($(CC), clang)
+  CFLAGS += -O3
+else
+  CFLAGS += -O6
+endif
 
 # Treat warnings as errors unless directed not to
 ifneq ($(WERROR),0)
diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 03cf947..2b941ef 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -144,8 +144,12 @@ ifndef DEBUG
 endif
 
 ifeq ($(DEBUG),0)
+ifeq ($(CC), clang)
+  CFLAGS += -O3
+else
   CFLAGS += -O6
 endif
+endif
 
 ifdef PARSER_DEBUG
   PARSER_DEBUG_BISON := -t