From 817480137a8b1165315f21d14b8968862101c3a2 Mon Sep 17 00:00:00 2001
From: Tony Cook <tony@develop-help.com>
Date: Tue, 28 Aug 2018 14:11:10 +1000
Subject: [PATCH] (perl #132158) abort compilation if we see an error compiling
 a form
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 t/lib/croak/toke | 9 +++++++++
 toke.c           | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/t/lib/croak/toke b/t/lib/croak/toke
index 59c377ba6b..21851229fe 100644
--- a/t/lib/croak/toke
+++ b/t/lib/croak/toke
@@ -493,3 +493,12 @@ sub t1 {}
 sub t2 (}
 EXPECT
 Prototype not terminated at - line 2.
+########
+# NAME [perl #132158] format with syntax errors
+format=
+@
+=h
+=cut
+EXPECT
+syntax error at - line 4, next token ???
+Execution of - aborted due to compilation errors.
diff --git a/toke.c b/toke.c
index 844de04a23..666424ba02 100644
--- a/toke.c
+++ b/toke.c
@@ -5099,6 +5099,14 @@ Perl_yylex(pTHX)
 
 	return yylex();
     case LEX_FORMLINE:
+        if (PL_parser->sub_error_count != PL_error_count) {
+            /* There was an error parsing a formline, which tends to
+               mess up the parser.
+               Unlike interpolated sub-parsing, we can't treat any of
+               these as recoverable, so no need to check sub_no_recover.
+            */
+            yyquit();
+        }
 	assert(PL_lex_formbrack);
 	s = scan_formline(PL_bufptr);
 	if (!PL_lex_formbrack)
@@ -6518,6 +6526,7 @@ Perl_yylex(pTHX)
 		SAVEI32(PL_lex_formbrack);
 		PL_parser->form_lex_state = PL_lex_state;
 		PL_lex_formbrack = PL_lex_brackets + 1;
+                PL_parser->sub_error_count = PL_error_count;
 		goto leftbracket;
 	    }
 	}
-- 
2.17.2