[LLVMdev] FreeBSD tester failure

[Jakob Stoklund Olesen]

On Sep 9, 2010, at 3:26 PM, Dimitry Andric wrote:

> On 2010-09-09 23:44, Jakob Stoklund Olesen wrote:
>> The clang-i686-freebsd-selfhost-rel buildbot is failing APIntTest.i33_Count on the first run, but the stage 2 test is passing.
>> 
>> It looks like it could be a miscompilation by the system gcc.
> 
> Yes, unfortunately on FreeBSD the first stage should be compiled using
> "-O2 -fno-strict-aliasing" instead of the default optimization flags, or
> this particular test will always fail.  Stage 2 (which is compiled by
> stage 1 clang) has no problems with it, and does not require
> -fno-strict-aliasing.
> 
> This is some obscure gcc 4.2.1 problem, but it is extremely hard to find
> out whether it really is an aliasing issue, or plainly a bug.  It is
> most likely the latter, since compiling with e.g. gcc 4.5 and -O3 did
> not give such failures, the last time I tried it (about two months ago,
> approximately).

Thanks,

Daniel, could this bot configure stage 1 with -fno-strict-aliasing?

Alternatively, if anybody knows a source workaround for this bug and/or aliasing issue...

> We should upgrade the system gcc on that machine, or stop testing the stage 1 llvm.
>> 
>> The tester is not useful as is. It is failing constantly.
>> 
>> Who owns this machine? Can the system be upgraded?
> 
> FreeBSD's gcc will probably never be upgraded past 4.2.1, because that
> was the last GPLv2 version.  This is one of the main reasons for getting
> clang in the tree... ;)

Makes sense.

/jakob