Error compiling with clang

Error compiling with clang

[Truls Becken]

Hi,

Compiling musl 0.9.0 with clang 3.0 gives me the following:

src/math/i386/llrint.s:5:2: error: invalid instruction mnemonic 'fistpq'

Changing fistpq back to fistpl in the 3 llrint files makes it compile.
Is this a bug in clang? How should it be resolved?

-Truls

Re: Error compiling with clang

[Rich Felker]

On Mon, May 07, 2012 at 10:13:06PM +0200, Truls Becken wrote:
> Hi,
> 
> Compiling musl 0.9.0 with clang 3.0 gives me the following:
> 
> src/math/i386/llrint.s:5:2: error: invalid instruction mnemonic 'fistpq'
> 
> Changing fistpq back to fistpl in the 3 llrint files makes it compile.
> Is this a bug in clang? How should it be resolved?

fistpl writes a 32-bit integer. This function needs a 64-bit integer
result. I'm pretty sure clang is just wrong here, but if there's an
alternate mnemonic for fistpq that works on clang and gcc/gas I'd be
happy to change it.

In the mean time, you can just remove that .s file so the C code gets
used.

Rich

Re: Error compiling with clang

[Szabolcs Nagy]

* Rich Felker <dalias@aerifal.cx> [2012-05-07 17:02:51 -0400]:
> alternate mnemonic for fistpq that works on clang and gcc/gas I'd be
> happy to change it.
> 

it seems clang recognizes fistpll instead of fistpq
(which works on gas as well)

Re: Error compiling with clang

[Szabolcs Nagy]

* Truls Becken <truls.becken@gmail.com> [2012-05-07 22:13:06 +0200]:
> Compiling musl 0.9.0 with clang 3.0 gives me the following:
> 
> src/math/i386/llrint.s:5:2: error: invalid instruction mnemonic 'fistpq'
> 
> Changing fistpq back to fistpl in the 3 llrint files makes it compile.
> Is this a bug in clang? How should it be resolved?
> 

in llrint you need the 64 bit int store instruction not the 32 bit one

it's either a bug in your as or clang
(although these instruction mnemonics are not documented)
here gnu as recognizes fistpq

Re: Error compiling with clang

[nwmcsween]

This is a bug with clang it wasn't implemented until recently, use svn

Sent from my iPhone

On May 7, 2012, at 1:13 PM, Truls Becken <truls.becken@gmail.com> wrote:

> Hi,
> 
> Compiling musl 0.9.0 with clang 3.0 gives me the following:
> 
> src/math/i386/llrint.s:5:2: error: invalid instruction mnemonic 'fistpq'
> 
> Changing fistpq back to fistpl in the 3 llrint files makes it compile.
> Is this a bug in clang? How should it be resolved?
> 
> -Truls

Re: Error compiling with clang

[Szabolcs Nagy]

* nwmcsween@gmail.com <nwmcsween@gmail.com> [2012-05-07 14:10:27 -0700]:
> This is a bug with clang it wasn't implemented until recently, use svn
> 
true, but the ll version works in earlier clangs as well
maybe it's better to use that one if every as recognizes it

http://llvm.org/viewvc/llvm-project?view=rev&revision=151543

Re: Error compiling with clang

[Rich Felker]

On Mon, May 07, 2012 at 11:18:51PM +0200, Szabolcs Nagy wrote:
> * nwmcsween@gmail.com <nwmcsween@gmail.com> [2012-05-07 14:10:27 -0700]:
> > This is a bug with clang it wasn't implemented until recently, use svn
> > 
> true, but the ll version works in earlier clangs as well
> maybe it's better to use that one if every as recognizes it

Indeed, I'll change it.

Rich

Re: Error compiling with clang

[Truls Becken]

On 2012-05-07, at 23:05, Szabolcs Nagy wrote:

> it's either a bug in your as or clang

I realized after sending the question that the issue would not be
with clang per se, but rather llvm-as.


On 2012-05-07, at 23:24, Rich Felker wrote:

> On Mon, May 07, 2012 at 11:18:51PM +0200, Szabolcs Nagy wrote:
> 
>> the ll version works in earlier clangs as well
>> maybe it's better to use that one if every as recognizes it
> 
> Indeed, I'll change it.

Thanks to everyone participating for resolving this. Supporting
clang 3.0, as opposed to a future point version, is a good thing.

I can now easily patch musl myself until the next release.

-Truls