Re: c++/7916

Re: c++/7916

[Wolfgang Bangerth]

The following reply was made to PR c++/7916; it has been noted by GNATS.

From: Wolfgang Bangerth <bangerth@ticam.utexas.edu>
To: gcc-gnats@gcc.gnu.org
Cc:  
Subject: Re: c++/7916
Date: Fri, 20 Dec 2002 20:43:24 -0600 (CST)

 ---------- Forwarded message ----------
 Date: Sat, 21 Dec 2002 01:19:12 +0100
 From: Jan Hubicka <jh@suse.cz>
 To: Janis Johnson <janis187@us.ibm.com>
 Cc: gcc@gcc.gnu.org, jh@suse.cz, bangerth@ticam.utexas.edu
 Subject: Re: patch that caused regression PR c++/7916
 
 > The regression reported in PR c++/7916 showed up starting with this
 > patch:
 > 
 > Wed Mar 14 22:26:10 CET 2001  Jan Hubicka  <jh@suse.cz>
 > 
 > 	* i386.c (ix86_cmodel_string, ix86_cmodel): Define.
 > 	(override_options): Parse cmodel string.
 > 	(x86_64_sign_extended_value, x86_64_zero_extended_value): New.
 > 	* i386.h (TARGET_OPTIONS): Add "cmodel".
 > 	(EXTRA_CONSTRAINT): Recognize 'e' and 'Z'.
 > 	(enum cmodel): New.
 > 	(ix86_cmodel_string, ix86_cmodel): Declare.
 > 
 > 	Spot by Matt Kraai:
 > 	* i386.h (GENERAL_REG_P): Add missing REG_P.
 > 
 > Here's a small test case that causes the compiler to ICE when compiled
 > on i686-linux.  The PR is against C++, but my testing used cc1 rather
 > than cc1plus.
 > 
 > -------------------
 > void foo(char *dst, char xchg, char cmp)
 > {
 >   __asm__("lock" "\tcmpxchgb %1, (%2)\t\n"
 >           :"=al"(cmp)
 >           :"dl"(xchg), "r"(dst), "al"(cmp));
 > }
 > -------------------
 > 
 > Output from the mainline compiler:
 > 
 > 7916.c: In function `foo':
 > 7916.c:6: internal compiler error: in instantiate_virtual_regs_1,
 >           at function.c:3898
 > Please submit a full bug report,
 > with preprocessed source if appropriate.
 > See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
 > 
 > I've added this information to the PR.
 > 
 > Jan, if the testcase itself isn't valid then please add that
 > information to the PR.
 The testcase is nonsenical ("=al" was probably meant to be "=a")
 but I will try to track down the reason for dying in
 instantiate_virtual_regs_1.  Thanks!
 
 Honza
 > 
 > Janis