|
|
Message-ID: <5342FF44.9060108@embtoolkit.org>
Date: Mon, 07 Apr 2014 21:40:52 +0200
From: Abdoulaye Walsimou Gaye <awg@...toolkit.org>
To: musl@...ts.openwall.com
Subject: Re: build with clang-3.4 warnings report
On 04/07/2014 07:23 PM, Rich Felker wrote:
> On Mon, Apr 07, 2014 at 11:17:55AM +0000, Oliver Schneider wrote:
>> On 2014-04-05 01:54, Rich Felker wrote:
>>>> src/env/__init_security.c:8:13: warning: function 'dummy' is not needed and will not be emitted [-Wunneeded-internal-declaration]
>>>> static void dummy(void *ent)
>>>> ^
>>>> 1 warning generated.
>>> This is a bug in the compiler; the function dummy has an externally
>>> visible alias, so it will not be omitted (and if it is actually
>>> omitted, that means the compiler is generating broken output).
>> There is yet another possibility ;)
>>
>> The ccc-analyzer could simply be buggy in this case. Would be
>> interesting to look at the optimized intermediate code whether this gets
>> optimized out. I think it probably doesn't, but who knows.
> At one point it was getting optimized out, which made it impossible to
> build musl with clang, so I think this was fixed and it's just a
> residual bug in the warning generation.
>
>> The dangling else warnings could also be resolved by simply adding
>> braces. It doesn't add to the code size, and the times when developers
>> where paid by LoC are long over (I hope).
>
Hello,
I can confirm that these functions are not optimized out by clang, here is __init_security.o example
16: 00000000 4 FUNC LOCAL DEFAULT 1 dummy
17: 00000000 24 OBJECT LOCAL DEFAULT 22 .L__init_security.pfd
18: 00000000 10 OBJECT LOCAL DEFAULT 23 .L.str
19: 00000000 0 SECTION LOCAL DEFAULT 22
20: 00000000 0 NOTYPE LOCAL DEFAULT 22 $d
21: 00000000 0 SECTION LOCAL DEFAULT 23
22: 00000000 0 SECTION LOCAL DEFAULT 24
23: 00000000 0 SECTION LOCAL DEFAULT 25
24: 00000000 0 SECTION LOCAL DEFAULT 26
25: 00000004 208 FUNC GLOBAL DEFAULT 1 __init_security
26: 00000000 4 FUNC WEAK DEFAULT 1 __init_ssp
27: 00000000 0 NOTYPE GLOBAL DEFAULT UND __syscall
28: 00000000 0 NOTYPE GLOBAL DEFAULT UND __libc
- awg
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.