1 files changed, 1 insertions, 1 deletions
diff --git a/toke.c b/toke.c
index f9e79fcf56..062909932a 100644
--- a/toke.c
+++ b/toke.c
@@ -6580,7 +6580,7 @@ Perl_yylex(pTHX)
 		    for (p = d; *p; ++p) {
 			if (!isSPACE(*p)) {
 			    d[tmp++] = *p;
-			    if (warnsyntax && !strchr("$@%*;[]&\\", *p))
+			    if (warnsyntax && !strchr("$@%*;[]&\\_", *p))
 				bad_proto = TRUE;
 			}
 		    }