c/7544: gcc does not output weak symbol unless declared

c/7544: gcc does not output weak symbol unless declared

[poulot]

>Number:         7544
>Category:       c
>Synopsis:       #pragma weak problem
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Thu Aug 08 13:06:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Benoit Poulot-Cazajous
>Release:        3.1.1 (Debian testing/unstable)
>Organization:
>Environment:
System: Linux walhalla 2.4.19 #2 Sat Aug 3 11:56:01 CEST 2002 i686 unknown unknown GNU/Linux
Architecture: i686

	
host: i386-pc-linux-gnu
build: i386-pc-linux-gnu
target: i386-pc-linux-gnu
configured with: /mnt/data/gcc-3.1/gcc-3.1-3.1.1ds3/src/configure -v --enable-languages=c,c++,java,f77,proto,objc,ada --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-gxx-include-dir=/usr/include/c++/-3.1 --enable-shared --with-system-zlib --enable-long-long --enable-nls --without-included-gettext --enable-clocale=gnu --enable-__cxa_atexit --enable-threads=posix --enable-java-gc=boehm --enable-objc-gc i386-linux
>Description:
When using '#pragma weak bar = foo', gcc does not output anything, unless
bar is declared.
gcc-2.95 and other compilers do not require such a declaration.
>How-To-Repeat:
		$ cat bug.c
#pragma weak bar = foo

		$ gcc-3.1 bug.c -S -o - 
        .file   "bug.c"
        .ident  "GCC: (GNU) 3.1.1"

		$ gcc-2.95 bug.c -S -o - 
        .file   "bug.c"
        .version        "01.01"
gcc2_compiled.:
        .weak   bar
        .set    bar,foo
        .ident  "GCC: (GNU) 2.95.4 20011002 (Debian prerelease)"

In order to get the correct output, bar() has to be declared :

		$ cat bug2.c
#pragma weak bar = foo
void bar();

		$ gcc-3.1 bug2.c -S -o -
        .file   "bug2.c"
        .weak   bar				<=== Ok !!!
        .set    bar,foo				<===/
        .ident  "GCC: (GNU) 3.1.1"

>Fix:

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