Created attachment 38918 [details]
config.log

so, it did built with '-j1' passed to make and with llvm support disabled.
but it was fruitless - it just installed 32 bit binaries into supplied libdir.

mklib: Making Linux static library:  libllvmpipe.a
ar: creating libllvmpipe.a
gcc -c -I. -I../../../../src/gallium/include -I../../../../src/gallium/auxiliary -I../../../../src/gallium/drivers  -g -O2 -Wall -Wmissing-prototypes -std=c99 -ffast-math -fvisibility=hidden -fno-strict-aliasing -m32  -fPIC -m32  -D_GNU_SOURCE -DPTHREADS -DHAVE_POSIX_MEMALIGN -DUSE_XCB -DUSE_EXTERNAL_DXTN_LIB=1 -DIN_DRI_DRIVER -DGLX_DIRECT_RENDERING -DGLX_INDIRECT_RENDERING -DHAVE_ALIAS -DHAVE_UDIS86 -DGALLIUM_LLVMPIPE -D__STDC_CONSTANT_MACROS -DHAVE_LLVM=0x0208 -I/usr/include  -DNDEBUG -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS lp_test_format.c -o lp_test_format.o
gcc -c -I. -I../../../../src/gallium/include -I../../../../src/gallium/auxiliary -I../../../../src/gallium/drivers  -g -O2 -Wall -Wmissing-prototypes -std=c99 -ffast-math -fvisibility=hidden -fno-strict-aliasing -m32  -fPIC -m32  -D_GNU_SOURCE -DPTHREADS -DHAVE_POSIX_MEMALIGN -DUSE_XCB -DUSE_EXTERNAL_DXTN_LIB=1 -DIN_DRI_DRIVER -DGLX_DIRECT_RENDERING -DGLX_INDIRECT_RENDERING -DHAVE_ALIAS -DHAVE_UDIS86 -DGALLIUM_LLVMPIPE -D__STDC_CONSTANT_MACROS -DHAVE_LLVM=0x0208 -I/usr/include  -DNDEBUG -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS lp_test_main.c -o lp_test_main.o
g++  -L/usr/lib64/llvm  -ludis86 -lpthread -lffi -ldl -lm  lp_test_format.o lp_test_main.o -o lp_test_format -Wl,--start-group  -L../../auxiliary/ -lgallium libllvmpipe.a -lLLVMBitWriter -lLLVMX86CodeGen -lLLVMX86Info -lLLVMX86AsmPrinter -lLLVMSelectionDAG -lLLVMAsmPrinter -lLLVMMCParser -lLLVMInterpreter -lLLVMJIT -lLLVMExecutionEngine -lLLVMCodeGen -lLLVMScalarOpts -lLLVMInstCombine -lLLVMTransformUtils -lLLVMipa -lLLVMAnalysis -lLLVMTarget -lLLVMMC -lLLVMCore -lLLVMSupport -lLLVMSystem -lstdc++ -ludis86  -lXext -lXdamage -lXfixes -lXxf86vm -lX11-xcb -lX11 -lxcb-glx -lxcb   -ldrm   -lm -lpthread -ldl -Wl,--end-group
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.1/../../../../x86_64-pc-linux-gnu/bin/ld: skipping incompatible ../../auxiliary//libgallium.a when searching for -lgallium
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.1/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lgallium
collect2: ld returned 1 exit status
gmake[4]: *** [lp_test_format] Error 1
gmake[4]: Leaving directory `/root/32bit/mesa/src/gallium/drivers/llvmpipe'
gmake[3]: *** [default] Error 1
gmake[3]: Leaving directory `/root/32bit/mesa/src/gallium/drivers'
gmake[2]: *** [default] Error 1
gmake[2]: Leaving directory `/root/32bit/mesa/src/gallium'
gmake[1]: *** [subdirs] Error 1
gmake[1]: Leaving directory `/root/32bit/mesa/src'
gmake: *** [default] Error 1

I can confirm that bug. 32bit build is OK, but WITHOUT LLVM. With LLVM end with exactly same error. llvm version is 2.8.

AFAIR Mesa has never supported building both 32 and 64 bit binaries at the same time. This should probably be handled more gracefully though.

never ? then what "--<switch>-32-bit --<switch>-64-bit" are for ? either those options should have been mutually exclusive from begin with or it should build all bunch of libraries as it were long time ago when i first tried it.

it probably can easily be fixed for non-llvm builds but with llvm two complications arise:
1) vendors don't have packages for 32bit llvm libs (or at least, Gentoo doesn't) and llvm don't seems to provide them as gcc does, for example
2) if llvm 32bit libraries would be provided by separate package they may be build not together with main llvm package and be of another, older version.

so, mesa building scripts should automatically check for native and llvm 32bit versions and configure them slightly differently (with llvm for native and no llvm support for 32bit if llvm 32bit not present, for example). it would be sweet.

ideally, i would just dropped mesa 32bit libs but because of wine and random non-opensource software (which both, unfortunately, are most demanding of graphic stack features and performance) i can't. no one can't :(
and in Gentoo you either sit with obsolete 32bit pre-built binaries or build your own by hacky and ugly ebuild which will never go official. clean way of doing so in mesa building scripts might help.

Gentoo have emul libs compiled WITH llvm... I personally asked for it :-))

they are ? good for them. but i still don't see 32bit llvm libraries lying anywhere so i could build _my_ mesa 32bit stuff in sync with my main mesa stuff and stop relying on some random fat package to deliver an obsolete 32bit mesa libs together with pile of other random libs.
not that it would help with current condition of handling multilib building in mesa.

Might want to read this mailing list thread I posted about using llvm on 32bit and 64bit builds. I seemed like it might be going somewhere and then it just died.

http://lists.freedesktop.org/archives/mesa-dev/2011-August/010941.html

multilib stuff is now fixed and documented in docs/autoconf.html.