Make parser_free() be called slightly later,

i.e. at the point where lexer vars are being restored in a LEAVE,
rather than at the end of yyparse()

p4raw-id: //depot/perl@30822

2 files changed, 21 insertions, 19 deletions

diff --git a/perly.c b/perly.c
index c8ee62ffc6..95779a014d 100644
--- a/perly.c
+++ b/perly.c
@@ -306,20 +306,6 @@ S_clear_yystack(pTHX_  const yy_parser *parser)
     }
 }
 
-/* delete a parser object */
-
-#ifndef PERL_IN_MADLY_C
-void
-Perl_parser_free(pTHX_  const yy_parser *parser)
-{
-    S_clear_yystack(aTHX_ parser);
-    Safefree(parser->stack);
-    Safefree(parser->lex_brackstack);
-    Safefree(parser->lex_casestack);
-    PL_parser = parser->old_parser;
-    Safefree(parser);
-}
-#endif
 
 /*----------.
 | yyparse.  |
@@ -362,8 +348,8 @@ Perl_yyparse (pTHX)
     parser = PL_parser;
     ps = parser->ps;
 
-    ENTER;  /* force parser free before we return */
-    SAVEPARSER(parser);
+    ENTER;  /* force parser stack cleanup before we return */
+    SAVEDESTRUCTOR_X(S_clear_yystack, parser);
 
 /*------------------------------------------------------------.
 | yynewstate -- Push a new state, which is found in yystate.  |
@@ -691,7 +677,7 @@ Perl_yyparse (pTHX)
     goto yyreturn;
 
   yyreturn:
-    LEAVE;			/* force parser free before we return */
+    LEAVE;	/* force parser stack cleanup before we return */
     return yyresult;
 }
 
diff --git a/toke.c b/toke.c
index a9e3d880a0..d11cdcc9b8 100644
--- a/toke.c
+++ b/toke.c
@@ -615,8 +615,7 @@ S_cr_textfilter(pTHX_ int idx, SV *sv, int maxlen)
 
 /*
  * Perl_lex_start
- * Initialize variables.  Uses the Perl save_stack to save its state (for
- * recursive calls to the parser).
+ * Create a parser object and initialise its parser and lexer fields
  */
 
 void
@@ -641,6 +640,9 @@ Perl_lex_start(pTHX_ SV *line)
     parser->yyerrstatus = 0;
     parser->yychar = YYEMPTY;		/* Cause a token to be read.  */
 
+    /* on scope exit, free this parser and restore any outer one */
+    SAVEPARSER(parser);
+
     /* initialise lexer state */
 
     SAVEI32(PL_lex_state);
@@ -713,6 +715,20 @@ Perl_lex_start(pTHX_ SV *line)
     PL_rsfp = 0;
 }
 
+
+/* delete a parser object */
+
+void
+Perl_parser_free(pTHX_  const yy_parser *parser)
+{
+    Safefree(parser->stack);
+    Safefree(parser->lex_brackstack);
+    Safefree(parser->lex_casestack);
+    PL_parser = parser->old_parser;
+    Safefree(parser);
+}
+
+
 /*
  * Perl_lex_end
  * Finalizer for lexing operations.  Must be called when the parser is