c/1964: code generation bug with -gdwarf-2 and -fPIC on x86

[crigler@hell-city.org]

>Number:         1964
>Category:       c
>Synopsis:       code generation bug with -gdwarf-2 and -fPIC on x86
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Tue Feb 13 10:16:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Ned T. Crigler
>Release:        2.97 20010211 (experimental)
>Organization:
>Environment:
System: Linux xavtug.hell-city.org 2.4.1-ac5 #1 Wed Feb 7 15:27:33 EST 2001 i686 unknown
Architecture: i686

	
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ./configure  --verbose --host=i686-pc-linux-gnu --target=i686-pc-linux-gnu --prefix=/usr/local/egcs --with-gcc-version-trigger=/usr/local/src/egcs/gcc/version.c --with-gnu-as --with-gnu-ld --with-system-zlib --enable-threads=posix --enable-languages=c++ --enable-shared --enable-libstdcxx-v3 --cache-file=../config.cache --with-dwarf2 --disable-nls : (reconfigured) 
>Description:

The PIC return address code is not placed in the .text section when DWARF2
debugging is used.

>How-To-Repeat:
Using gcc -mcpu=i686 -gdwarf-2 -g -fPIC on:

void
foo()
{
}

int
main()
{
	foo();
	return 0;
}

produces:
        .section        .debug_aranges
        .4byte  0x1c
        .2byte  0x2
        .4byte  .Ldebug_info0
        .byte   0x4
        .byte   0x0
        .2byte  0x0,0
        .4byte  .Ltext0
        .4byte  .Letext0-.Ltext0
        .4byte  0x0
        .4byte  0x0
.LPR0:
        movl    (%esp), %ebx
        ret
        .ident  "GCC: (GNU) 2.97 20010212 (experimental)"

The .LPR0 code is placed in the .debug_aranges section, instead of the .text
section. Since debugging sections aren't loaded at runtime, the program
crashes.

>Fix:
	
>Release-Note:
>Audit-Trail:
>Unformatted: