[tip:perf/core] perf intel-pt-decoder: Avoid checking code drift on busibox's diff

[tip-bot for Arnaldo Carvalho de Melo]

Commit-ID:  c8a3f7de76717a994c208e137156c077b1e93092
Gitweb:     http://git.kernel.org/tip/c8a3f7de76717a994c208e137156c077b1e93092
Author:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Tue, 12 Jul 2016 12:16:35 -0300
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Tue, 12 Jul 2016 15:20:41 -0300

perf intel-pt-decoder: Avoid checking code drift on busibox's diff

That doesn't have -I to match lines.

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-7nz9hnbk7a9p91ou927ye5yh@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/intel-pt-decoder/Build | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/intel-pt-decoder/Build b/tools/perf/util/intel-pt-decoder/Build
index 0611d61..9b742ea 100644
--- a/tools/perf/util/intel-pt-decoder/Build
+++ b/tools/perf/util/intel-pt-decoder/Build
@@ -7,8 +7,11 @@ $(OUTPUT)util/intel-pt-decoder/inat-tables.c: $(inat_tables_script) $(inat_table
 	$(call rule_mkdir)
 	@$(call echo-cmd,gen)$(AWK) -f $(inat_tables_script) $(inat_tables_maps) > $@ || rm -f $@
 
+# Busybox's diff doesn't have -I, avoid warning in the case
+
 $(OUTPUT)util/intel-pt-decoder/intel-pt-insn-decoder.o: util/intel-pt-decoder/intel-pt-insn-decoder.c util/intel-pt-decoder/inat.c $(OUTPUT)util/intel-pt-decoder/inat-tables.c
-	@(test -d ../../kernel -a -d ../../tools -a -d ../perf && (( \
+	@(diff -I 2>&1 | grep -q 'option requires an argument' && \
+	test -d ../../kernel -a -d ../../tools -a -d ../perf && (( \
 	diff -B -I'^#include' util/intel-pt-decoder/insn.c ../../arch/x86/lib/insn.c >/dev/null && \
 	diff -B -I'^#include' util/intel-pt-decoder/inat.c ../../arch/x86/lib/inat.c >/dev/null && \
 	diff -B util/intel-pt-decoder/x86-opcode-map.txt ../../arch/x86/lib/x86-opcode-map.txt >/dev/null && \