On Thu, 9 Nov 2006, Joel E. Denny wrote: > I switched to Flex 2.5.33, and now I see the same results as you. (I > didn't bother testing my original patch this time.) I'll investigate > solutions later.
I committed the following patch, which appears to fix it. Please review my change to translate_action in scan-code.l. I removed a couple of lines that don't appear to do any harm but also don't appear to serve any purpose. Index: ChangeLog =================================================================== RCS file: /sources/bison/bison/ChangeLog,v retrieving revision 1.1602 diff -p -u -r1.1602 ChangeLog --- ChangeLog 9 Nov 2006 18:17:05 -0000 1.1602 +++ ChangeLog 10 Nov 2006 05:17:37 -0000 @@ -1,5 +1,19 @@ 2006-11-10 Joel E. Denny <[EMAIL PROTECTED]> + Fix memory leaks in scanners generated by at least Flex 2.5.9 and + later. Reported by Paul Eggert in + <http://lists.gnu.org/archive/html/bison-patches/2006-11/msg00014.html>. + * src/flex-scanner.h (yylex_destroy): Define for Flex before 2.5.9. + * src/scan-code.l (translate_action): Don't bother invoking + yy_delete_buffer (YY_CURRENT_BUFFER) before creating the first buffer. + (code_scanner_free): Instead of invoking + yy_delete_buffer (YY_CURRENT_BUFFER) directly, invoke yylex_destroy, + which frees more. + * src/scan-gram.l (gram_scanner_free): Likewise. + * src/scan-skel.l (scan_skel): Likewise. + +2006-11-09 Joel E. Denny <[EMAIL PROTECTED]> + * src/files.c (tr): Change return type to void. * src/muscle_tab.c (muscle_insert): Free storage in case muscle_grow has been called previously for the same key. Index: src/flex-scanner.h =================================================================== RCS file: /sources/bison/bison/src/flex-scanner.h,v retrieving revision 1.5 diff -p -u -r1.5 flex-scanner.h --- src/flex-scanner.h 10 Aug 2006 04:53:04 -0000 1.5 +++ src/flex-scanner.h 10 Nov 2006 05:17:37 -0000 @@ -50,6 +50,19 @@ int FLEX_PREFIX (lex_destroy) (void); # define yytext FLEX_PREFIX (text) #endif +/* Non-reentrant scanners generated by Flex 2.5.9 and later (and some earlier + versions according to the Flex manual) leak memory if yylex_destroy is not + invoked. However, yylex_destroy is not defined before Flex 2.5.9, so give + an implementation here that at least appears to work with Flex 2.5.4. */ +#if !defined(YY_FLEX_MAJOR_VERSION) || YY_FLEX_MAJOR_VERSION < 2 \ + || (YY_FLEX_MAJOR_VERSION == 2 \ + && (!defined(YY_FLEX_MINOR_VERSION) || YY_FLEX_MINOR_VERSION < 5 \ + || (YY_FLEX_MINOR_VERSION == 5 \ + && (!defined(YY_FLEX_SUBMINOR_VERSION) \ + || YY_FLEX_SUBMINOR_VERSION < 9)))) +# define yylex_destroy() yy_delete_buffer (YY_CURRENT_BUFFER) +#endif + /* OBSTACK_FOR_STRING -- Used to store all the characters that we need to keep (to construct ID, STRINGS etc.). Use the following macros to use it. Index: src/scan-code.l =================================================================== RCS file: /sources/bison/bison/src/scan-code.l,v retrieving revision 1.14 diff -p -u -r1.14 scan-code.l --- src/scan-code.l 8 Nov 2006 20:28:57 -0000 1.14 +++ src/scan-code.l 10 Nov 2006 05:17:37 -0000 @@ -380,8 +380,6 @@ translate_action (int sc_context, symbol if (!initialized) { obstack_init (&obstack_for_string); - /* The initial buffer, never used. */ - yy_delete_buffer (YY_CURRENT_BUFFER); yy_flex_debug = 0; initialized = true; } @@ -422,5 +420,5 @@ code_scanner_free (void) { obstack_free (&obstack_for_string, 0); /* Reclaim Flex's buffers. */ - yy_delete_buffer (YY_CURRENT_BUFFER); + yylex_destroy (); } Index: src/scan-gram.l =================================================================== RCS file: /sources/bison/bison/src/scan-gram.l,v retrieving revision 1.107 diff -p -u -r1.107 scan-gram.l --- src/scan-gram.l 8 Nov 2006 20:28:57 -0000 1.107 +++ src/scan-gram.l 10 Nov 2006 05:17:37 -0000 @@ -800,5 +800,5 @@ gram_scanner_free (void) { obstack_free (&obstack_for_string, 0); /* Reclaim Flex's buffers. */ - yy_delete_buffer (YY_CURRENT_BUFFER); + yylex_destroy (); } Index: src/scan-skel.l =================================================================== RCS file: /sources/bison/bison/src/scan-skel.l,v retrieving revision 1.41 diff -p -u -r1.41 scan-skel.l --- src/scan-skel.l 10 Aug 2006 04:53:04 -0000 1.41 +++ src/scan-skel.l 10 Nov 2006 05:17:37 -0000 @@ -121,5 +121,5 @@ scan_skel (FILE *in) skel__flex_debug = trace_flag & trace_skeleton; skel_lex (); /* Reclaim Flex's buffers. */ - yy_delete_buffer (YY_CURRENT_BUFFER); + yylex_destroy (); }
