netpbm needs to use standard intel interfaces rather than gcc __builtins

[pmetzger (Perry E. Metzger)]

It appears that clang lacks some of the intrinsics supplied by gcc, and that building netpbm under xcode 4.4 results in the following error message. This is rather important, as netpbm is a dependency of many packages.

/usr/bin/clang -c -I.  -Iimportinc -Iimportinc/netpbm -I/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_netpbm/netpbm/work/advanced/editor/pamflip  -DNDEBUG  -I/opt/local/include -O3 -arch x86_64    -o pamflip_sse.o pamflip_sse.c
pamflip_sse.c:136:39: error: use of unknown builtin '__builtin_ia32_pcmpeqb128' [-Wimplicit-function-declaration]
        register v16qi const compare =__builtin_ia32_pcmpeqb128(vReg,zero128);
                                      ^
pamflip_sse.c:136:30: error: initializing 'const v16qi' with an expression of incompatible type 'int'
        register v16qi const compare =__builtin_ia32_pcmpeqb128(vReg,zero128);
                             ^        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2 errors generated.
gnumake[2]: *** [pamflip_sse.o] Error 1
gnumake[2]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_netpbm/netpbm/work/advanced/editor/pamflip'

[nerdling (Jeremy Lavergne)]

OP believes that clang is missing an sse intrinsic from gcc.

[jeremyhu (Jeremy Huddleston Sequoia)]

Since ML is now out, I can now discuss this.

netpbm needs to change. clang is behaving correctly. netpbm assumes that it has access to __builtin_ia32_pcmpeqb128, but it doesn't. clang dropped suport for the GCC-specific builtin and now supports the standard _mm_cmpeq_epi8.

<rdar://problem/11858813>

[jeremyhu (Jeremy Huddleston Sequoia)]

r95870 should work around the issue for now, but it should still be fixed.

[neverpanic (Clemens Lang)]

Jeremy, do you want to take this upstream? Other than the line you wrote I have no idea what the problem is about, but you seem to have more information. The website suggests mailing to the local part bryanh below giraffe-data.com.

[neverpanic (Clemens Lang)]

Has duplicate #35156.

[jmroot (Joshua Root)]

See ​http://clang.llvm.org/compatibility.html#vector_builtins

[ryandesign (Ryan Carsten Schmidt)]

Replying to jeremyhu@…:

r95870 should work around the issue for now, but it should still be fixed.

In netpbm 10.60.00 they changed their check to no longer try to use these GCC-specific functions with clang so I removed the patch in r112197.

Replying to cal@…:

Jeremy, do you want to take this upstream? Other than the line you wrote I have no idea what the problem is about, but you seem to have more information. The website suggests mailing to the local part bryanh below giraffe-data.com.

I emailed the developer about this.

[cooljeanius (Eric Gallager)]

Cc Me!

[neverpanic (Clemens Lang)]

So this seems to be fixed.