perf tools: Add "reject" option for parse-events.l

Commit-ID:  b6af53b7d6fa40262c16753fe2781a3e792d5e1b
Gitweb:     https://git.kernel.org/tip/b6af53b7d6fa40262c16753fe2781a3e792d5e1b
Author:     Jiri Olsa <[email protected]>
AuthorDate: Wed, 8 Nov 2017 16:43:09 +0100
Committer:  Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Thu, 9 Nov 2017 10:09:03 -0300

perf tools: Add "reject" option for parse-events.l

Arnaldo reported broken builds in some distros using a newer flex release, 2.6.4, found in Alpine Linux 3.6 and Edge, with flex not spotting the REJECT macro:

CC /tmp/build/perf/util/parse-events-flex.o
util/parse-events.l: In function 'parse_events_lex':
/tmp/build/perf/util/parse-events-flex.c:4734:16: error: \
'reject_used_but_not_detected' undeclared (first use in this function)

It's happening because we put the REJECT under another USER_REJECT macro in following commit:

9445464bb831 perf tools: Unwind properly location after REJECT

Fortunately flex provides option for force it to use REJECT, adding it to parse-events.l.

---
 tools/perf/util/parse-events.l | 1 +
 1 file changed, 1 insertion(+)

index 6680e4f..dc5f40e 100644
@@ -5,6 +5,7 @@
 %option stack
 %option bison-locations
 %option yylineno
+%option reject
 
 %{
 #include <errno.h>