Fix for [perl #20339]: "%lf" rejected as invalid by recent sprintf.

Now allows but ignores the 'l' modifier on floating point formats
and adds a couple of tests.

p4raw-id: //depot/perl@18689

1 files changed, 3 insertions, 2 deletions

diff --git a/sv.c b/sv.c
index 6eef6264cc..37e1492816 100644
--- a/sv.c
+++ b/sv.c
@@ -8813,6 +8813,9 @@ Perl_sv_vcatpvfn(pTHX_ SV *sv, const char *pat, STRLEN patlen, va_list *args, SV
 		intsize = 'q';
 #endif
 		break;
+/* [perl #20339] - we should accept and ignore %hf, %lf rather than die */
+	    case 'l':
+		/* FALL THROUGH */
 	    default:
 #if defined(USE_LONG_DOUBLE)
 		intsize = args ? 0 : 'q';
@@ -8825,8 +8828,6 @@ Perl_sv_vcatpvfn(pTHX_ SV *sv, const char *pat, STRLEN patlen, va_list *args, SV
 		/* FALL THROUGH */
 #endif
 	    case 'h':
-		/* FALL THROUGH */
-	    case 'l':
 		goto unknown;
 	    }