From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16375 invoked by alias); 7 Dec 2001 21:17:29 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 16313 invoked from network); 7 Dec 2001 21:17:26 -0000 Received: from unknown (HELO zwingli.cygnus.com) (208.245.165.35) by sources.redhat.com with SMTP; 7 Dec 2001 21:17:26 -0000 Received: by zwingli.cygnus.com (Postfix, from userid 442) id 3D2835E9D8; Fri, 7 Dec 2001 16:18:44 -0500 (EST) To: gdb-patches@sources.redhat.com Subject: Re: RFA: GCC stabs don't contain prototype info References: <20011127034423.DF2B75E9D8@zwingli.cygnus.com> From: Jim Blandy Date: Fri, 07 Dec 2001 13:17:00 -0000 In-Reply-To: Jim Blandy's message of Mon, 26 Nov 2001 22:44:23 -0500 (EST) Message-ID: X-Mailer: Gnus v5.3/Emacs 19.34 X-SW-Source: 2001-12/txt/msg00208.txt.bz2 I've committed this change. Jim Blandy writes: > This comes as a bit of a surprise to me, but it seems that stabs > generated by GCC don't indicate whether a given function was defined > with a prototype or not. The argument types should appear after the > return types, each preceded by a semicolon, but for the following > input program: > > int foo (int a, float b) { return a + b; } > > `gcc -save-temps -O2 -g -c' generates the following relevant stabs: > > .stabs "int:t(0,1)=r(0,1);0020000000000;0017777777777;",128,0,0,0 > .stabs "float:t(0,12)=r(0,1);4;0;",128,0,0,0 > .stabs "foo:F(0,1)",36,0,1,foo > .stabs "a:P(0,1)",64,0,1,8 > .stabs "b:P(0,12)",64,0,1,9 > .stabs "",36,0,0,.LLscope0-foo > .stabs "",100,0,0,.Letext > > There is no no prototype info here. There's no way for GDB to know > that the function expects its second argument to be passed as a float, > not promoted to a double, as the K&R-style rules specify. > > Thus: > > 2001-11-26 Jim Blandy > > * gdb.base/callfuncs.exp: The stabs generated by GCC don't tell us > whether functions are prototyped or not, so we can't possibly pass > arguments to t_float_values2 properly. > > Index: gdb/testsuite/gdb.base/callfuncs.exp > =================================================================== > RCS file: /cvs/cvsfiles/devo/gdb/testsuite/gdb.base/callfuncs.exp,v > retrieving revision 1.46 > diff -c -r1.46 callfuncs.exp > *** gdb/testsuite/gdb.base/callfuncs.exp 2001/11/10 00:08:23 1.46 > --- gdb/testsuite/gdb.base/callfuncs.exp 2001/11/27 03:24:59 > *************** > *** 142,147 **** > --- 142,150 ---- > gdb_test "p t_float_values(float_val1,-2.3765)" " = 1" > > # Test passing of arguments which might not be widened. > + # Under stabs, GCC doesn't tell us whether the function was > + # prototyped or not. > + if {$gcc_compiled} { setup_xfail_format "stabs" } > gdb_test "p t_float_values2(0.0,0.0)" " = 0" > > # Although PR 5318 mentions SunOS specifically, this seems > *************** > *** 152,158 **** > --- 155,166 ---- > setup_xfail "alpha-dec-osf2*" "i*86-*-sysv4*" 5318 > } > } > + > + # Under stabs, GCC doesn't tell us whether the function was > + # prototyped or not. > + if {$gcc_compiled} { setup_xfail_format "stabs" } > gdb_test "p t_float_values2(3.14159,float_val2)" " = 1" > + > gdb_test "p t_small_values(1,2,3,4,5,6,7,8,9,10)" " = 55" > > gdb_test "p t_double_values(0.0,0.0)" " = 0" > *************** > *** 289,294 **** > --- 297,304 ---- > } > } > } > + > + get_debug_format > > # Make sure that malloc gets called and that the floating point unit > # is initialized via a call to t_double_values. >