Fix some possible-use-of-uninitialized warnings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80515 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/regcomp.c b/lib/Support/regcomp.c
index 4fd88b1..2755fd8 100644
--- a/lib/Support/regcomp.c
+++ b/lib/Support/regcomp.c
@@ -1419,8 +1419,8 @@
 findmust(struct parse *p, struct re_guts *g)
 {
 	sop *scan;
-	sop *start;    /* start initialized in the default case, after that */
-	sop *newstart; /* newstart was initialized in the OCHAR case */
+	sop *start = 0; /* start initialized in the default case, after that */
+	sop *newstart = 0; /* newstart was initialized in the OCHAR case */
 	sopno newlen;
 	sop s;
 	char *cp;