"panic: MUTEX_LOCK" in blead, but not in maint
Marcus Holland-Moritz
currently run a binary search to find out which patch causes it. I
also cannot provide a small testcase because I don't fully understand
the problem.
I just synced blead and maint and out of usual habit tried to build
my CPAN modules with them. Building Convert-Binary-C-0.49 with blead,
I'm getting
mhx@r2d2 ~/src/perl/Convert-Binary-C/0.49 $ bleadperl -Mblib t/114_cache.t
1..72
# Running under perl version 5.009 for linux
# Current time local: Fri Feb 27 19:34:29 2004
# Current time GMT: Fri Feb 27 18:34:29 2004
# Using Test.pm version 1.24
ok 1
[...]
ok 71
# failed to create Convert::Binary::C::Cached object
# panic: MUTEX_LOCK at /home/mhx/src/perl/Convert-Binary-C/0.49/blib/lib/Convert/Binary/C/Cached.pm line 233.
# failed to create Convert::Binary::C::Cached object
# panic: MUTEX_LOCK at /home/mhx/src/perl/Convert-Binary-C/0.49/blib/lib/Convert/Binary/C/Cached.pm line 233.
# failed to create Convert::Binary::C::Cached object
# panic: MUTEX_LOCK at /home/mhx/src/perl/Convert-Binary-C/0.49/blib/lib/Convert/Binary/C/Cached.pm line 233.
# failed to create Convert::Binary::C::Cached object
# panic: MUTEX_LOCK at /home/mhx/src/perl/Convert-Binary-C/0.49/blib/lib/Convert/Binary/C/Cached.pm line 233.
# failed to create Convert::Binary::C::Cached object
# panic: MUTEX_LOCK at /home/mhx/src/perl/Convert-Binary-C/0.49/blib/lib/Convert/Binary/C/Cached.pm line 233.
Segmentation fault
when running the t/114_cache.t test. There's no such problem with maint.
I rebuilt blead with debugging enabled and patched the MUTEX_LOCK
macro to include __FILE__ and __LINE__ and figured that the panic
is coming from op_free(). So I rewrote that part to be able to set
a breakpoint:
--- op.c.orig 2004-02-27 19:41:01.000000000 +0100
+++ op.c 2004-02-27 19:41:22.000000000 +0100
@@ -227,7 +227,11 @@
case OP_LEAVE:
case OP_SCOPE:
case OP_LEAVEWRITE:
- OP_REFCNT_LOCK;
+ {
+ int rv;
+ if ((rv = pthread_mutex_lock(&PL_op_mutex)) != 0)
+ Perl_croak_nocontext("PANIC: MUTEX_LOCK (%d)", rv);
+ }
if (OpREFCNT_dec(o)) {
OP_REFCNT_UNLOCK;
return;
Here's the relevant part of the gdb session:
mhx@r2d2 ~/src/perl/Convert-Binary-C/0.49 $ gdb bleadperl-debug
GNU gdb 6.0
Copyright 2003 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i686-pc-linux-gnu"...Using host libthread_db library "/lib/libthread_db.so.1".
(gdb) b op.c:233
Breakpoint 1 at 0x8099299: file op.c, line 233.
(gdb) r -Mblib t/114_cache.t
Starting program: /home/mhx/apps/bin/bleadperl-debug -Mblib t/114_cache.t
[Thread debugging using libthread_db enabled]
[New Thread 16384 (LWP 29251)]
1..72
# Running under perl version 5.009001 for linux
# Current time local: Fri Feb 27 19:44:37 2004
# Current time GMT: Fri Feb 27 18:44:37 2004
# Using Test.pm version 1.24
ok 1
[...]
ok 71
[Switching to Thread 16384 (LWP 29251)]
Breakpoint 1, Perl_op_free (my_perl=0x81b0eb8, o=0x82a9498) at op.c:233
233 Perl_croak_nocontext("PANIC: MUTEX_LOCK (%d)", rv);
(gdb) bt
#0 Perl_op_free (my_perl=0x81b0eb8, o=0x82a9498) at op.c:233
#1 0x080a4925 in Perl_cv_undef (my_perl=0x81b0eb8, cv=0x83922e4) at op.c:3863
#2 0x080fcafb in Perl_sv_clear (my_perl=0x81b0eb8, sv=0x83922e4) at sv.c:5459
#3 0x080fd1f2 in Perl_sv_free2 (my_perl=0x81b0eb8, sv=0x83922e4) at sv.c:5667
#4 0x080fccda in Perl_sv_clear (my_perl=0x81b0eb8, sv=0x8392434) at sv.c:5497
#5 0x080fd1f2 in Perl_sv_free2 (my_perl=0x81b0eb8, sv=0x8392434) at sv.c:5667
#6 0x080d549a in Perl_magic_setsig (my_perl=0x81b0eb8, sv=0x8287a88, mg=0x81d0558) at mg.c:1340
#7 0x080d2404 in Perl_mg_set (my_perl=0x81b0eb8, sv=0x8287a88) at mg.c:210
#8 0x08126e5e in Perl_leave_scope (my_perl=0x81b0eb8, base=46) at scope.c:788
#9 0x08124afa in Perl_pop_scope (my_perl=0x81b0eb8) at scope.c:137
#10 0x08130cc3 in Perl_pp_leaveloop (my_perl=0x81b0eb8) at pp_ctl.c:1863
#11 0x080c98a2 in Perl_runops_debug (my_perl=0x81b0eb8) at dump.c:1563
#12 0x08066638 in S_run_body (my_perl=0x81b0eb8, oldscope=1) at perl.c:1724
#13 0x080660aa in perl_run (my_perl=0x81b0eb8) at perl.c:1647
#14 0x0805fcd4 in main (argc=3, argv=0xbffff1e4, env=0xbffff1f4) at perlmain.c:86
(gdb) p rv
$1 = 22
So the error code returned by pthread_mutex_lock() is 22:
mhx@r2d2 ~ $ grep -P '\b22\b' /usr/include/asm/errno.h
#define EINVAL 22 /* Invalid argument */
Which according to the manpage means that the mutex hasn't been properly
initialized:
ERRORS
The pthread_mutex_lock function returns the following error code on error:
EINVAL the mutex has not been properly initialized.
The code which seems to be causing the trouble looks like this:
[...]
my(@warnings, $error);
{
local $SIG{__WARN__} = sub { push @warnings, $_[0] };
if( $_[0] eq 'file' ) {
eval { $self->SUPER::parse_file( $_[1] ) };
}
else {
eval { $self->SUPER::parse( $_[1] ) };
}
}
[...]
The panic occurs right after the block is left (I guess) from what
I can tell from the debug output:
([...]/lib/Convert/Binary/C/Cached.pm:233) enterloop
([...]/lib/Convert/Binary/C/Cached.pm:233) nextstate
([...]/lib/Convert/Binary/C/Cached.pm:233) pushmark
([...]/lib/Convert/Binary/C/Cached.pm:233) anoncode
([...]/lib/Convert/Binary/C/Cached.pm:233) refgen
([...]/lib/Convert/Binary/C/Cached.pm:233) gv(main::SIG)
([...]/lib/Convert/Binary/C/Cached.pm:233) rv2hv
([...]/lib/Convert/Binary/C/Cached.pm:233) const(PV("__WARN__"\0))
([...]/lib/Convert/Binary/C/Cached.pm:233) helem
([...]/lib/Convert/Binary/C/Cached.pm:233) sassign
([...]/lib/Convert/Binary/C/Cached.pm:233) nextstate
([...]/lib/Convert/Binary/C/Cached.pm:235) aelemfast
([...]/lib/Convert/Binary/C/Cached.pm:235) const(PV("file"\0))
([...]/lib/Convert/Binary/C/Cached.pm:235) seq
([...]/lib/Convert/Binary/C/Cached.pm:235) cond_expr
([...]/lib/Convert/Binary/C/Cached.pm:235) enter
([...]/lib/Convert/Binary/C/Cached.pm:235) nextstate
([...]/lib/Convert/Binary/C/Cached.pm:239) entertry
([...]/lib/Convert/Binary/C/Cached.pm:239) nextstate
([...]/lib/Convert/Binary/C/Cached.pm:239) pushmark
([...]/lib/Convert/Binary/C/Cached.pm:239) padsv($self)
([...]/lib/Convert/Binary/C/Cached.pm:239) gv(main::_)
([...]/lib/Convert/Binary/C/Cached.pm:239) rv2av
([...]/lib/Convert/Binary/C/Cached.pm:239) const(IV(1))
([...]/lib/Convert/Binary/C/Cached.pm:239) aelem
([...]/lib/Convert/Binary/C/Cached.pm:239) const(PV("SUPER::parse"\0))
([...]/lib/Convert/Binary/C/Cached.pm:239) method
([...]/lib/Convert/Binary/C/Cached.pm:239) entersub
([...]/lib/Convert/Binary/C/Cached.pm:239) leavetry
([...]/lib/Convert/Binary/C/Cached.pm:239) leave
([...]/lib/Convert/Binary/C/Cached.pm:235) leaveloop
[Switching to Thread 16384 (LWP 29377)]
Breakpoint 1, Perl_op_free (my_perl=0x81b0eb8, o=0x82aa868) at op.c:233
233 Perl_croak_nocontext("PANIC: MUTEX_LOCK (%d)", rv);
At this point, I'm lost. Here's my perl configuration:
mhx@r2d2 ~/src/perl/dist/rsync/perl-current $ bleadperl-debug -V
Summary of my perl5 (revision 5 version 9 subversion 1 patch 22397) configuration:
Platform:
osname=linux, osvers=2.4.22-gentoo-r4, archname=i686-linux-thread-multi
uname='linux r2d2 2.4.22-gentoo-r4 #1 thu jan 29 20:01:30 met 2004 i686 intel(r) pentium(r) iii mobile cpu 1000mhz genuineintel gnulinux '
config_args='-des -Dusedevel -Dusethreads -Dnoextensions=Encode -Dprefix=/home/mhx/perl/blead-debug -Doptimize=-g -Dcc=gcc-3.4'
hint=recommended, useposix=true, d_sigaction=define
usethreads=define useithreads=define usemultiplicity=define
useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
use64bitint=undef use64bitall=undef uselongdouble=undef
usemymalloc=n, bincompat5005=undef
Compiler:
cc='gcc-3.4', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBUGGING -fno-strict-aliasing -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
optimize='-g',
cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBUGGING -fno-strict-aliasing'
ccversion='', gccversion='3.4.0 20031224 (experimental)', gccosandvers=''
intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
alignbytes=4, prototype=define
Linker and Libraries:
ld='gcc-3.4', ldflags =' -L/usr/local/lib'
libpth=/usr/local/lib /lib /usr/lib
libs=-lnsl -lndbm -lgdbm -ldb -ldl -lm -lcrypt -lutil -lpthread -lc
perllibs=-lnsl -ldl -lm -lcrypt -lutil -lpthread -lc
libc=/lib/libc-2.3.2.so, so=so, useshrplib=false, libperl=libperl.a
gnulibc_version='2.3.2'
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
cccdlflags='-fpic', lddlflags='-shared -L/usr/local/lib'
Characteristics of this binary (from libperl):
Compile-time options: DEBUGGING MULTIPLICITY USE_ITHREADS USE_LARGE_FILES PERL_IMPLICIT_CONTEXT
Locally applied patches:
DEVEL21538
Built under linux
Compiled at Feb 27 2004 18:51:59
@INC:
/home/mhx/perl/blead-debug/lib/5.9.1/i686-linux-thread-multi
/home/mhx/perl/blead-debug/lib/5.9.1
/home/mhx/perl/blead-debug/lib/site_perl/5.9.1/i686-linux-thread-multi
/home/mhx/perl/blead-debug/lib/site_perl/5.9.1
/home/mhx/perl/blead-debug/lib/site_perl
.
Building Convert-Binary-C is easy. It doesn't have an prerequisites
and should just "work" (perl Makefile.PL && make). Just get the latest
version (0.49) from CPAN if you want to try to reproduce the problem.
Marcus
--
I know it's weird, but it does make it easier to write poetry in perl. :-)
--Larry Wall in <78...@jpl-devvax.JPL.NASA.GOV>
Marcus Holland-Moritz
> I'm a bit lost in finding the cause for this problem and I cannot
> currently run a binary search to find out which patch causes it. I
> also cannot provide a small testcase because I don't fully understand
> the problem.
>
> [...]
Ok, after downloading APC a binary search showed that change #22302
is causing the trouble. That was the switch from byacc to bison.
Unfortunately, I still don't have an idea. I thought that it might
have been a problem that Convert::Binary::C is also using two bison
parsers, but examining the code I don't see why it should.
Dave?
Marcus
--
BOFH Excuse #112:
The monitor is plugged into the serial port
Dave Mitchell
> On 2004-02-27, at 20:12:07 +0100, Marcus Holland-Moritz wrote:
>
> > I'm a bit lost in finding the cause for this problem and I cannot
> > currently run a binary search to find out which patch causes it. I
> > also cannot provide a small testcase because I don't fully understand
> > the problem.
> >
> > [...]
>
> Ok, after downloading APC a binary search showed that change #22302
> is causing the trouble. That was the switch from byacc to bison.
I've found the problem - Perl_yylex_r() isn't (and never has been!)
threadsafe. Am working on a fix.
Dave.
--
print+qq&$}$"$/$s$,$*${d}$g$s$@$.$q$,$:$.$q$^$,$@$*$~$;$.$q$m&if+map{m,^\d{0\,},,${$::{$'}}=chr($"+=$&||1)}q&10m22,42}6:17*2~2.3@3;^2dg3q/s"&=~m*\d\*.*g
Marcus Holland-Moritz
> On Sat, Feb 28, 2004 at 11:56:46AM +0100, Marcus Holland-Moritz wrote:
> > On 2004-02-27, at 20:12:07 +0100, Marcus Holland-Moritz wrote:
> >
> > > I'm a bit lost in finding the cause for this problem and I cannot
> > > currently run a binary search to find out which patch causes it. I
> > > also cannot provide a small testcase because I don't fully understand
> > > the problem.
> > >
> > > [...]
> >
> > Ok, after downloading APC a binary search showed that change #22302
> > is causing the trouble. That was the switch from byacc to bison.
>
> I've found the problem - Perl_yylex_r() isn't (and never has been!)
> threadsafe. Am working on a fix.
Just a couple of minutes ago I've also tracked it down to Perl_yylex_r()...
However, I don't think it's (only) a thread-safety issue. The problem is
that continuously eval()ing wrong code seems to blow the parser stack. The
'panic: YYMAXLEVEL' is trapped in $@. yyactlevel permanently increases
until
yylval_pointer[yyactlevel] = lvalp;
overwrites the contents of PL_op_mutex, which will in turn cause the
"panic: MUTEX_LOCK" later.
BTW, here's a shorter "pure perl" test case:
mhx@r2d2 ~ $ bleadperl-debug -e'for (1..200) { eval "\x1"; my $w; local $_ = sub {$w} }'
PANIC: MUTEX_LOCK (22) at -e line 1.
Attempt to free unreferenced scalar: SV 0x81b1a14.
PANIC: MUTEX_LOCK (22).
Interestingly this also triggers a "Attempt to free...".
Marcus
--
What the scientists have in their briefcases is terrifying.
-- Nikita Khruschev
Nicholas Clark
> Just a couple of minutes ago I've also tracked it down to Perl_yylex_r()...
>
> However, I don't think it's (only) a thread-safety issue. The problem is
> that continuously eval()ing wrong code seems to blow the parser stack. The
> 'panic: YYMAXLEVEL' is trapped in $@. yyactlevel permanently increases
> until
>
> yylval_pointer[yyactlevel] = lvalp;
>
> overwrites the contents of PL_op_mutex, which will in turn cause the
> "panic: MUTEX_LOCK" later.
>
> BTW, here's a shorter "pure perl" test case:
>
> mhx@r2d2 ~ $ bleadperl-debug -e'for (1..200) { eval "\x1"; my $w; local $_ = sub {$w} }'
> PANIC: MUTEX_LOCK (22) at -e line 1.
> Attempt to free unreferenced scalar: SV 0x81b1a14.
> PANIC: MUTEX_LOCK (22).
>
> Interestingly this also triggers a "Attempt to free...".
Valgrind might help:
==5979== pthread_mutex_lock/trylock: mutex is invalid
==5979== at 0x402B1EA3: __pthread_mutex_lock (vg_libpthread.c:944)
==5979== by 0x8099045: Perl_op_free (op.c:230)
==5979== by 0x80A4606: Perl_cv_undef (op.c:3859)
==5979== by 0x80FBFCC: Perl_sv_clear (sv.c:5459)
panic: MUTEX_LOCK at -e line 1.
==5979== warning: Valgrind's siglongjmp is incomplete
==5979== (it ignores cleanup handlers)
==5979== your program may misbehave as a result
Attempt to free unreferenced scalar: SV 0x41942e0c.
==5979==
==5979== pthread_mutex_lock/trylock: mutex is invalid
==5979== at 0x402B1EA3: __pthread_mutex_lock (vg_libpthread.c:944)
==5979== by 0x8099045: Perl_op_free (op.c:230)
==5979== by 0x8061EDD: perl_destruct (perl.c:361)
==5979== by 0x805FD34: main (perlmain.c:88)
panic: MUTEX_LOCK.
I didn't get a panic without running it under valgrind. Maybe I didn't wait
long enough.
Nicholas Clark
Dave Mitchell
> On 2004-02-28, at 16:36:51 +0000, Dave Mitchell wrote:
>
> > On Sat, Feb 28, 2004 at 11:56:46AM +0100, Marcus Holland-Moritz wrote:
> > > On 2004-02-27, at 20:12:07 +0100, Marcus Holland-Moritz wrote:
> > >
> > > > I'm a bit lost in finding the cause for this problem and I cannot
> > > > currently run a binary search to find out which patch causes it. I
> > > > also cannot provide a small testcase because I don't fully understand
> > > > the problem.
> > > >
> > > > [...]
> > >
> > > Ok, after downloading APC a binary search showed that change #22302
> > > is causing the trouble. That was the switch from byacc to bison.
> >
> > I've found the problem - Perl_yylex_r() isn't (and never has been!)
> > threadsafe. Am working on a fix.
>
> Just a couple of minutes ago I've also tracked it down to Perl_yylex_r()...
>
> However, I don't think it's (only) a thread-safety issue. The problem is
> that continuously eval()ing wrong code seems to blow the parser stack. The
> 'panic: YYMAXLEVEL' is trapped in $@. yyactlevel permanently increases
> until
Yes, I'm aware of this :-) I'm in the process of excising yylex_r from
bleed even as we speak.
--
The Enterprise successfully ferries an alien VIP from one place to another
without serious incident.
-- Things That Never Happen in "Star Trek" #7
Dave Mitchell
Now fixed by the change below (hopefully).
--
This email is confidential, and now that you have read it you are legally
obliged to shoot yourself. Or shoot a lawyer, if you prefer. If you have
received this email in error, place it in its original wrapping and return
for a full refund. By opening this email, you accept that Elvis lives.
Change 22408 by davem@davem-percy on 2004/02/28 22:37:08
make the bison-based parser threadsafe and capable of deep
recursion by eradicating Perl_yylex_r()
Affected files ...
... //depot/perl/embed.fnc#123 edit
... //depot/perl/embed.h#434 edit
... //depot/perl/embedvar.h#186 edit
... //depot/perl/intrpvar.h#140 edit
... //depot/perl/mg.c#294 edit
... //depot/perl/perl.h#552 edit
... //depot/perl/perlapi.h#107 edit
... //depot/perl/perly.c#62 edit
... //depot/perl/proto.h#472 edit
... //depot/perl/toke.c#494 edit
Differences ...
==== //depot/perl/embed.fnc#123 (text) ====
@@ -853,9 +853,6 @@
Ap |I32 |whichsig |char* sig
p |void |write_to_stderr|const char* message|int msglen
p |int |yyerror |char* s
-#ifdef USE_PURE_BISON
-p |int |yylex_r |YYSTYPE *lvalp|int *lcharp
-#endif
p |int |yylex
p |int |yyparse
p |int |yywarn |char* s
==== //depot/perl/embed.h#434 (text+w) ====
@@ -1138,11 +1138,6 @@
#ifdef PERL_CORE
#define yyerror Perl_yyerror
#endif
-#ifdef USE_PURE_BISON
-#ifdef PERL_CORE
-#define yylex_r Perl_yylex_r
-#endif
-#endif
#ifdef PERL_CORE
#define yylex Perl_yylex
#endif
@@ -3640,11 +3635,6 @@
#ifdef PERL_CORE
#define yyerror(a) Perl_yyerror(aTHX_ a)
#endif
-#ifdef USE_PURE_BISON
-#ifdef PERL_CORE
-#define yylex_r(a,b) Perl_yylex_r(aTHX_ a,b)
-#endif
-#endif
#ifdef PERL_CORE
#define yylex() Perl_yylex(aTHX)
#endif
==== //depot/perl/embedvar.h#186 (text+w) ====
@@ -457,6 +457,8 @@
#define PL_xpvnv_root (vTHX->Ixpvnv_root)
#define PL_xrv_arenaroot (vTHX->Ixrv_arenaroot)
#define PL_xrv_root (vTHX->Ixrv_root)
+#define PL_yycharp (vTHX->Iyycharp)
+#define PL_yylvalp (vTHX->Iyylvalp)
#else /* !MULTIPLICITY */
@@ -756,6 +758,8 @@
#define PL_Ixpvnv_root PL_xpvnv_root
#define PL_Ixrv_arenaroot PL_xrv_arenaroot
#define PL_Ixrv_root PL_xrv_root
+#define PL_Iyycharp PL_yycharp
+#define PL_Iyylvalp PL_yylvalp
#define PL_TSv PL_Sv
#define PL_TXpv PL_Xpv
==== //depot/perl/intrpvar.h#140 (text) ====
@@ -396,6 +396,10 @@
PERLVAR(Ilast_swash_tmps, U8 *)
PERLVAR(Ilast_swash_slen, STRLEN)
+/* perly.c globals */
+PERLVAR(Iyycharp, int *)
+PERLVAR(Iyylvalp, YYSTYPE *)
+
PERLVARI(Iglob_index, int, 0)
PERLVAR(Isrand_called, bool)
PERLVARA(Iuudmap,256, char)
==== //depot/perl/mg.c#294 (text) ====
@@ -566,9 +566,6 @@
case '\004': /* ^D */
sv_setiv(sv, (IV)(PL_debug & DEBUG_MASK));
-#if defined(YYDEBUG) && defined(DEBUGGING)
- PL_yydebug = DEBUG_p_TEST;
-#endif
break;
case '\005': /* ^E */
if (*(mg->mg_ptr+1) == '\0') {
==== //depot/perl/perl.h#552 (text) ====
@@ -11,12 +11,6 @@
#ifndef H_PERL
#define H_PERL 1
-/* XXX DAPM tmp - always do this now - probably nedd to remove all trace
- * of the define at some pooint. Feb 04 */
-
-#define USE_PURE_BISON 1
-
-
#ifdef PERL_FOR_X2P
/*
* This file is being used for x2p stuff.
==== //depot/perl/perlapi.h#107 (text+w) ====
@@ -672,6 +672,10 @@
#define PL_xrv_arenaroot (*Perl_Ixrv_arenaroot_ptr(aTHX))
#undef PL_xrv_root
#define PL_xrv_root (*Perl_Ixrv_root_ptr(aTHX))
+#undef PL_yycharp
+#define PL_yycharp (*Perl_Iyycharp_ptr(aTHX))
+#undef PL_yylvalp
+#define PL_yylvalp (*Perl_Iyylvalp_ptr(aTHX))
#undef PL_Sv
#define PL_Sv (*Perl_TSv_ptr(aTHX))
#undef PL_Xpv
==== //depot/perl/perly.c#62 (text) ====
@@ -76,10 +76,6 @@
#define YYTERROR 1
#define YYERRCODE 256
-/* YYLEX -- calling `yylex' with the right arguments. */
-
-# define YYLEX yylex_r (&yylval, &yychar)
-
/* Enable debugging if requested. */
#ifdef DEBUGGING
@@ -335,11 +331,12 @@
YYDPRINTF ((Perl_debug_log, "Starting parse\n"));
-#ifdef USE_ITHREADS
- /* XXX is this needed anymore? DAPM 13-Feb-04;
- * if not, delete the correspinding LEAVE too */
ENTER; /* force stack free before we return */
-#endif
+ SAVEVPTR(PL_yycharp);
+ SAVEVPTR(PL_yylvalp);
+ PL_yycharp = &yychar; /* so PL_yyerror() can access it */
+ PL_yylvalp = &yylval; /* so various functions in toke.c can access it */
+
yyss_sv = NEWSV(73, YYINITDEPTH * sizeof(short));
yyvs_sv = NEWSV(73, YYINITDEPTH * sizeof(YYSTYPE));
SAVEFREESV(yyss_sv);
@@ -437,7 +434,12 @@
/* YYCHAR is either YYEMPTY or YYEOF or a valid lookahead symbol. */
if (yychar == YYEMPTY) {
YYDPRINTF ((Perl_debug_log, "Reading a token: "));
- yychar = YYLEX;
+ yychar = yylex();
+# ifdef EBCDIC
+ if (yychar >= 0 && yychar < 255) {
+ yychar = NATIVE_TO_ASCII(yychar);
+ }
+# endif
}
if (yychar <= YYEOF) {
@@ -722,9 +724,7 @@
yyreturn:
-#ifdef USE_ITHREADS
- LEAVE; /* force stack free before we return */
-#endif
+ LEAVE; /* force stack free before we return */
return yyresult;
}
==== //depot/perl/proto.h#472 (text+w) ====
@@ -815,9 +815,6 @@
PERL_CALLCONV I32 Perl_whichsig(pTHX_ char* sig);
PERL_CALLCONV void Perl_write_to_stderr(pTHX_ const char* message, int msglen);
PERL_CALLCONV int Perl_yyerror(pTHX_ char* s);
-#ifdef USE_PURE_BISON
-PERL_CALLCONV int Perl_yylex_r(pTHX_ YYSTYPE *lvalp, int *lcharp);
-#endif
PERL_CALLCONV int Perl_yylex(pTHX);
PERL_CALLCONV int Perl_yyparse(pTHX);
PERL_CALLCONV int Perl_yywarn(pTHX_ char* s);
==== //depot/perl/toke.c#494 (text) ====
@@ -23,8 +23,8 @@
#define PERL_IN_TOKE_C
#include "perl.h"
-#define yychar PL_yychar
-#define yylval PL_yylval
+#define yychar (*PL_yycharp)
+#define yylval (*PL_yylvalp)
static char ident_too_long[] = "Identifier too long";
static char c_without_g[] = "Use of /c modifier is meaningless without /g";
@@ -79,22 +79,6 @@
#undef ff_next
#endif
-#ifdef USE_PURE_BISON
-# ifndef YYMAXLEVEL
-# define YYMAXLEVEL 100
-# endif
-YYSTYPE* yylval_pointer[YYMAXLEVEL];
-int* yychar_pointer[YYMAXLEVEL];
-int yyactlevel = -1;
-# undef yylval
-# undef yychar
-# define yylval (*yylval_pointer[yyactlevel])
-# define yychar (*yychar_pointer[yyactlevel])
-# define PERL_YYLEX_PARAM yylval_pointer[yyactlevel],yychar_pointer[yyactlevel]
-# undef yylex
-# define yylex() Perl_yylex_r(aTHX_ yylval_pointer[yyactlevel],yychar_pointer[yyactlevel])
-#endif
-
#include "keywords.h"
/* CLINE is a macro that ensures PL_copline has a sane value */
@@ -2176,32 +2160,7 @@
if we already built the token before, use it.
*/
-#ifdef USE_PURE_BISON
-int
-Perl_yylex_r(pTHX_ YYSTYPE *lvalp, int *lcharp)
-{
- int r;
-
- yyactlevel++;
- yylval_pointer[yyactlevel] = lvalp;
- yychar_pointer[yyactlevel] = lcharp;
- if (yyactlevel >= YYMAXLEVEL)
- Perl_croak(aTHX_ "panic: YYMAXLEVEL");
-
- r = Perl_yylex(aTHX);
-# ifdef EBCDIC
- if (r >= 0 && r < 255) {
- r = NATIVE_TO_ASCII(r);
- }
-# endif
-
- if (yyactlevel > 0)
- yyactlevel--;
- return r;
-}
-#endif
-
#ifdef __SC__
#pragma segment Perl_yylex
#endif
@@ -7802,12 +7761,7 @@
}
else if (yychar > 255)
where = "next token ???";
-#ifdef USE_PURE_BISON
-/* GNU Bison sets the value -2 */
- else if (yychar == -2) {
-#else
- else if ((yychar & 127) == 127) {
-#endif
+ else if (yychar == -2) { /* YYEMPTY */
if (PL_lex_state == LEX_NORMAL ||
(PL_lex_state == LEX_KNOWNEXT && PL_lex_defer == LEX_NORMAL))
where = "at end of line";
Marcus Holland-Moritz
> On Sat, Feb 28, 2004 at 06:53:41PM +0000, Dave Mitchell wrote:
> > On Sat, Feb 28, 2004 at 06:56:10PM +0100, Marcus Holland-Moritz wrote:
> > > On 2004-02-28, at 16:36:51 +0000, Dave Mitchell wrote:
> > > > I've found the problem - Perl_yylex_r() isn't (and never has been!)
> > > > threadsafe. Am working on a fix.
> > >
> > > Just a couple of minutes ago I've also tracked it down to Perl_yylex_r()...
> > >
> > > However, I don't think it's (only) a thread-safety issue. The problem is
> > > that continuously eval()ing wrong code seems to blow the parser stack. The
> > > 'panic: YYMAXLEVEL' is trapped in $@. yyactlevel permanently increases
> > > until
> >
> >
> > Yes, I'm aware of this :-) I'm in the process of excising yylex_r from
> > bleed even as we speak.
> >
> > --
> > The Enterprise successfully ferries an alien VIP from one place to another
> > without serious incident.
> > -- Things That Never Happen in "Star Trek" #7
>
>
> Now fixed by the change below (hopefully).
Very nice!
Marcus
--
birth, n:
The first and direst of all disasters.
-- Ambrose Bierce, "The Devil's Dictionary"