[cfe-commits] r127594 - in /cfe/trunk: lib/CodeGen/CodeGenModule.cpp test/CodeGen/darwin-string-literals.c

[Rafael Espíndola]

On 14 March 2011 14:37, Chris Lattner <clattner at apple.com> wrote:
>
> On Mar 14, 2011, at 10:55 AM, Rafael Espindola wrote:
>
>> Author: rafael
>> Date: Mon Mar 14 12:55:00 2011
>> New Revision: 127594
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=127594&view=rev
>> Log:
>> Fix link of libxul with LTO and the linker in xcode4. It is not clear if this
>> is working around a bug in ld or if the new linker has a reasonable reason
>> for wanting the string constant to be linker visible.
>
> Hi Rafael,
>
> Private is probably the wrong answer, but I think that LinkerPrivate is the right answer.  Does LinkerPrivate work for libxul?

Bringing up an old thread now that I know Nick's email :-)

Nick, can you confirm if this a real requirement by the linker of if
it was a bug in that version? The issue is that given

const char *foo() {
  return "foo";
}
const void *bar() {
  return __builtin___CFStringMakeConstantString("bar");
}

both "foo" and "bar" get put in __TEXT,__cstring,cstring_literals, but
with different symbol styles:

L_.str:
        .asciz  "foo"
l_.str1:
        .asciz  "bar"

Why does the linker need a visible symbol for "bar"? Doesn't an offset
into the section tells it all that it needs to know: this relocations
points to the string "bar".

Cheers,
Rafael