From owner-freebsd-bugs Wed Apr 24 9:21:15 2002 Delivered-To: freebsd-bugs@hub.freebsd.org Received: from freefall.freebsd.org (freefall.FreeBSD.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id 7B88D37B41C for ; Wed, 24 Apr 2002 09:21:00 -0700 (PDT) Received: (from gnats@localhost) by freefall.freebsd.org (8.11.6/8.11.6) id g3OGK1g64570; Wed, 24 Apr 2002 09:20:01 -0700 (PDT) (envelope-from gnats) Received: from h132-197-179-27.gte.com (h132-197-179-27.gte.com [132.197.179.27]) by hub.freebsd.org (Postfix) with ESMTP id C1D3C37B417 for ; Wed, 24 Apr 2002 09:13:31 -0700 (PDT) Received: from kanpc.gte.com (localhost [IPv6:::1]) by h132-197-179-27.gte.com (8.12.3/8.12.3) with ESMTP id g3OGDO9B028838 for ; Wed, 24 Apr 2002 12:13:24 -0400 (EDT) (envelope-from ak03@kanpc.gte.com) Received: (from ak03@localhost) by kanpc.gte.com (8.12.3/8.12.3/Submit) id g3OGDOuq028837; Wed, 24 Apr 2002 12:13:24 -0400 (EDT) Message-Id: <200204241613.g3OGDOuq028837@kanpc.gte.com> Date: Wed, 24 Apr 2002 12:13:24 -0400 (EDT) From: Alexander Kabaev Reply-To: Alexander Kabaev To: FreeBSD-gnats-submit@FreeBSD.org X-Send-Pr-Version: 3.113 Subject: gnu/37423: GCC C++ frontend fixes for OpenOffice Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org >Number: 37423 >Category: gnu >Synopsis: GCC C++ frontend fixes for OpenOffice >Confidential: no >Severity: serious >Priority: medium >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Wed Apr 24 09:20:01 PDT 2002 >Closed-Date: >Last-Modified: >Originator: Alexander N. Kabaev >Release: FreeBSD 5.0-CURRENT i386 >Organization: Verizon Data Services >Environment: System: FreeBSD kanpc.gte.com 5.0-CURRENT FreeBSD 5.0-CURRENT #6: Tue Apr 16 10:42:42 EDT 2002 root@kanpc.gte.com:/usr/src/sys/i386/compile/KANPC i386 gcc version 2.95.4 20020320 [FreeBSD] >Description: I had to make the following changes to our system gcc to stop it from miscompiling OpenOffice code: 1. Changes to integrate.c deal with the problem, demonstrated by the code in the How To Repeat section below. If inline function which uses exception handling is being integrated into a function, which does not itself contain any try/catch constructs, several global flags values are not set correctly. The urrent_function_has_nonlocal_label flags is not getting set in particular. This allows GCC to allocate registers across function calls. When exception is thrown in called functions, the exception handler is reached with global registers (ebx, edi, esi) content clobbered without gcc ever noticing that. The STLPort test suite failure was caused by exactly this bug. 2. Changes in expr.c fix the problem demonstrated by the second code snippet below. I did not make a complete test case with nice printfs out of it, but if you compile it with g++ -O -S and then look into assembly code, you will notice rogue 'add $16, %esp' assembly instruction in return case. GCC defers adjusting stack pointer after function calls until absolutely necessary, but sometimes fails to do in at the right time. In this case, the bogus stack pointer adjustment is a leftover from a __cp_push_exception call done as a part of the throw statement processing. In DWARF2 case stack was getting adjusted at the right time as a side effect of expand_eh_region_end. sjlj-exceptions do not use this function so I added a call to do_pending_stack_adjust in its place. Alternatively, stack adjustment could be done right before a call to __sjthrow is expanded, but I think the current patch keeps us closer to DWARF2-based exceptions code flow. One nice side effect of this approach is that 'add $16, %esp' is getting optimized away at the first flow optimization pass as non-reachable. This patch fixes the problem with saxparser found by Martin Blapp. >How-To-Repeat: The following code demonstrates the problem #1: ================= Begin ==================== void do_nothing() { __asm ("movl $0, %%esi" : : :"%esi"); throw 5; } int __inline crash() { register int test = 0; try { test = 35; do_nothing(); } catch(...) { test--; } return test; } extern "C" int printf(const char *, ...); void main() { int ret = crash(); printf("%d\n", ret); } ================= End ==================== This example demonstrates the problem #2. Not as complete as the first example, you will need to compile it to assembly. Look for the following asembly fragment: movl -120(%ebp),%edx movl 4(%edx),%eax movl 4(%eax),%edx movl (%edx),%edx movl %edx,4(%eax) addl $16,%esp # <== This add is bogus addl $-12,%esp # Pushing arguments to guard_operate movl -124(%ebp),%eax # will stomp over saved registers pushl %eax # Here goes calling function's EBX :) call guard_operate__FP5Guard movl -120(%ebp),%edx movl 4(%edx),%eax movl (%eax),%eax movl %eax,4(%edx) ================= Begin ==================== class Guard; void guard_operate(Guard *pG); class Guard { public: Guard() { guard_operate(this); } ~Guard() { guard_operate(this); } }; class SimpleRegistryImpl { public: SimpleRegistryImpl(); ~SimpleRegistryImpl(); virtual void open() throw(int); }; extern int flag; void SimpleRegistryImpl::open( ) throw(int) { __asm("int3;"); Guard aGuard; if ( flag ) { return; } throw 5; } ================= End ==================== >Fix: Index: integrate.c =================================================================== RCS file: /home/ncvs/src/contrib/gcc.295/integrate.c,v retrieving revision 1.1.1.3 diff -u -r1.1.1.3 integrate.c --- integrate.c 16 Oct 1999 06:05:22 -0000 1.1.1.3 +++ integrate.c 31 Mar 2002 05:51:24 -0000 @@ -1608,6 +1608,20 @@ if (FUNCTION_FLAGS (header) & FUNCTION_FLAGS_NEEDS_CONTEXT) static_chain_value = lookup_static_chain (fndecl); + /* If the inline function has these flags sets, that means that + coresponding global flags should be set for this function. */ + if (FUNCTION_FLAGS (header) & FUNCTION_FLAGS_CALLS_SETJMP) + current_function_calls_setjmp = 1; + + if (FUNCTION_FLAGS (header) & FUNCTION_FLAGS_CALLS_LONGJMP) + current_function_calls_longjmp = 1; + + if (FUNCTION_FLAGS (header) & FUNCTION_FLAGS_HAS_NONLOCAL_LABEL) + current_function_has_nonlocal_label = 1; + + if (FUNCTION_FLAGS (header) & FUNCTION_FLAGS_USES_CONST_POOL) + current_function_uses_const_pool = 1; + if (GET_CODE (parm_insns) == NOTE && NOTE_LINE_NUMBER (parm_insns) > 0) { Index: stmt.c =================================================================== RCS file: /home/ncvs/src/contrib/gcc.295/stmt.c,v retrieving revision 1.1.1.6 diff -u -r1.1.1.6 stmt.c --- stmt.c 17 Feb 2001 08:36:08 -0000 1.1.1.6 +++ stmt.c 21 Apr 2002 06:07:51 -0000 @@ -4027,6 +4027,10 @@ cleanup = protect_with_terminate (cleanup); expand_eh_region_end (cleanup); } + else + { + do_pending_stack_adjust(); + } } if (reachable) >Release-Note: >Audit-Trail: >Unformatted: To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message