grep: don't redundantly compile throwaway patterns under threading

diff --git a/builtin/grep.c b/builtin/grep.c
index b1095362fbf9a4726367b96e0f34d38faf27d9bd..12e62fcbf3edaaeeaa5577a81d1a4f3b7bd09a28 100644 (file)
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -224,7 +224,8 @@ static void start_threads(struct grep_opt *opt)
                int err;
                struct grep_opt *o = grep_opt_dup(opt);
                o->output = strbuf_out;
-               o->debug = 0;
+               if (i)
+                       o->debug = 0;
                compile_grep_patterns(o);
                err = pthread_create(&threads[i], NULL, run, o);
 
@@ -1167,8 +1168,6 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
        if (!opt.fixed && opt.ignore_case)
                opt.regflags |= REG_ICASE;
 
-       compile_grep_patterns(&opt);
-
        /*
         * We have to find "--" in a separate pass, because its presence
         * influences how we will parse arguments that come before it.
@@ -1245,6 +1244,15 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
        num_threads = 0;
 #endif
 
+       if (!num_threads)
+               /*
+                * The compiled patterns on the main path are only
+                * used when not using threading. Otherwise
+                * start_threads() below calls compile_grep_patterns()
+                * for each thread.
+                */
+               compile_grep_patterns(&opt);
+
 #ifndef NO_PTHREADS
        if (num_threads) {
                if (!(opt.name_only || opt.unmatch_name_only || opt.count)