Zig is failing to build for m68k-freestanding-eabi

[TeamPuzel]

Zig Version

0.12.0-dev.3498+aff71c613

Steps to Reproduce and Observed Behavior

I built Zig and LLVM with the m68k target enabled, however Zig fails to build or even emit assembly for m68k-freestanding-eabi.

error: error(llvm): LLVM failed to parse 'm68k-unknown-unknown-eabi': Unable to find target for this triple (no targets are registered)
error: InvalidLlvmTriple

That's still confusing as the built clang can definitely emit assembly for the target zig is passing to llvm.

The command I used:

zig build-obj -fno-emit-bin -femit-asm=add.s -target m68k-freestanding-eabi ./src/main.zig

Expected Behavior

LLVM has support for this and the llvm/clang I built with m68k support when building Zig does accept this target, so I would expect Zig to also accept it.

[nektro]

did you build zig with -Dllvm-has-m68k ?

[TeamPuzel]

Okay, I now tried doing that, this happened:

15:08 zig > /Users/teampuzel/Downloads/zig-macos-aarch64-0.12.0-dev.3518+d2be725e4/zig build -p stage3 --search-prefix "/Users/teampuzel/local/llvm17-release" --search-prefix "$(brew --prefix zstd)" --zig-lib-dir lib -Dstatic-llvm -Dllvm-has-m68k -Doptimize=ReleaseSafe
install
└─ install zig
   └─ zig build-exe zig ReleaseSafe native 5 errors
error: undefined symbol: _LLVMInitializeM68kAsmParser
    note: referenced by /Users/teampuzel/local/llvm17-release/lib/liblldELF.a(Driver.cpp.o):__ZN4llvm23InitializeAllAsmParsersEv
    note: referenced by /Users/teampuzel/OpenSource/zig/zig-cache/o/ad0e2c9095df7909c490603aa6dfaf75/zig.o:_codegen.llvm.initializeLLVMTarget
error: undefined symbol: _LLVMInitializeM68kTarget
    note: referenced by /Users/teampuzel/local/llvm17-release/lib/liblldELF.a(Driver.cpp.o):__ZN4llvm20InitializeAllTargetsEv
    note: referenced by /Users/teampuzel/OpenSource/zig/zig-cache/o/ad0e2c9095df7909c490603aa6dfaf75/zig.o:_codegen.llvm.initializeLLVMTarget
error: undefined symbol: _LLVMInitializeM68kTargetInfo
    note: referenced by /Users/teampuzel/local/llvm17-release/lib/liblldELF.a(Driver.cpp.o):__ZN4llvm24InitializeAllTargetInfosEv
    note: referenced by /Users/teampuzel/OpenSource/zig/zig-cache/o/ad0e2c9095df7909c490603aa6dfaf75/zig.o:_codegen.llvm.initializeLLVMTarget
error: undefined symbol: _LLVMInitializeM68kTargetMC
    note: referenced by /Users/teampuzel/local/llvm17-release/lib/liblldELF.a(Driver.cpp.o):__ZN4llvm22InitializeAllTargetMCsEv
    note: referenced by /Users/teampuzel/OpenSource/zig/zig-cache/o/ad0e2c9095df7909c490603aa6dfaf75/zig.o:_codegen.llvm.initializeLLVMTarget
error: undefined symbol: _LLVMInitializeM68kAsmPrinter
    note: referenced by /Users/teampuzel/local/llvm17-release/lib/liblldELF.a(Driver.cpp.o):__ZN4llvm24InitializeAllAsmPrintersEv
    note: referenced by /Users/teampuzel/OpenSource/zig/zig-cache/o/ad0e2c9095df7909c490603aa6dfaf75/zig.o:_codegen.llvm.initializeLLVMTarget
error: the following command failed with 5 compilation errors:
/Users/teampuzel/Downloads/zig-macos-aarch64-0.12.0-dev.3518+d2be725e4/zig build-exe --stack 33554432 -cflags -std=c++17 -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -D_GNU_SOURCE -fvisibility-inlines-hidden -fno-exceptions -fno-rtti -Werror=type-limits -Wno-missing-braces -Wno-comment -DNDEBUG=1 -- /Users/teampuzel/OpenSource/zig/src/zig_llvm.cpp /Users/teampuzel/OpenSource/zig/src/zig_clang.cpp /Users/teampuzel/OpenSource/zig/src/zig_llvm-ar.cpp /Users/teampuzel/OpenSource/zig/src/zig_clang_driver.cpp /Users/teampuzel/OpenSource/zig/src/zig_clang_cc1_main.cpp /Users/teampuzel/OpenSource/zig/src/zig_clang_cc1as_main.cpp -lclangFrontendTool -lclangCodeGen -lclangFrontend -lclangDriver -lclangSerialization -lclangSema -lclangStaticAnalyzerFrontend -lclangStaticAnalyzerCheckers -lclangStaticAnalyzerCore -lclangAnalysis -lclangASTMatchers -lclangAST -lclangParse -lclangBasic -lclangEdit -lclangLex -lclangARCMigrate -lclangRewriteFrontend -lclangRewrite -lclangCrossTU -lclangIndex -lclangToolingCore -lclangExtractAPI -lclangSupport -llldMinGW -llldELF -llldCOFF -llldWasm -llldMachO -llldCommon -lLLVMWindowsManifest -lLLVMXRay -lLLVMLibDriver -lLLVMDlltoolDriver -lLLVMCoverage -lLLVMLineEditor -lLLVMXCoreDisassembler -lLLVMXCoreCodeGen -lLLVMXCoreDesc -lLLVMXCoreInfo -lLLVMX86TargetMCA -lLLVMX86Disassembler -lLLVMX86AsmParser -lLLVMX86CodeGen -lLLVMX86Desc -lLLVMX86Info -lLLVMWebAssemblyDisassembler -lLLVMWebAssemblyAsmParser -lLLVMWebAssemblyCodeGen -lLLVMWebAssemblyUtils -lLLVMWebAssemblyDesc -lLLVMWebAssemblyInfo -lLLVMVEDisassembler -lLLVMVEAsmParser -lLLVMVECodeGen -lLLVMVEDesc -lLLVMVEInfo -lLLVMSystemZDisassembler -lLLVMSystemZAsmParser -lLLVMSystemZCodeGen -lLLVMSystemZDesc -lLLVMSystemZInfo -lLLVMSparcDisassembler -lLLVMSparcAsmParser -lLLVMSparcCodeGen -lLLVMSparcDesc -lLLVMSparcInfo -lLLVMRISCVTargetMCA -lLLVMRISCVDisassembler -lLLVMRISCVAsmParser -lLLVMRISCVCodeGen -lLLVMRISCVDesc -lLLVMRISCVInfo -lLLVMPowerPCDisassembler -lLLVMPowerPCAsmParser -lLLVMPowerPCCodeGen -lLLVMPowerPCDesc -lLLVMPowerPCInfo -lLLVMNVPTXCodeGen -lLLVMNVPTXDesc -lLLVMNVPTXInfo -lLLVMMSP430Disassembler -lLLVMMSP430AsmParser -lLLVMMSP430CodeGen -lLLVMMSP430Desc -lLLVMMSP430Info -lLLVMMipsDisassembler -lLLVMMipsAsmParser -lLLVMMipsCodeGen -lLLVMMipsDesc -lLLVMMipsInfo -lLLVMLoongArchDisassembler -lLLVMLoongArchAsmParser -lLLVMLoongArchCodeGen -lLLVMLoongArchDesc -lLLVMLoongArchInfo -lLLVMLanaiDisassembler -lLLVMLanaiCodeGen -lLLVMLanaiAsmParser -lLLVMLanaiDesc -lLLVMLanaiInfo -lLLVMHexagonDisassembler -lLLVMHexagonCodeGen -lLLVMHexagonAsmParser -lLLVMHexagonDesc -lLLVMHexagonInfo -lLLVMBPFDisassembler -lLLVMBPFAsmParser -lLLVMBPFCodeGen -lLLVMBPFDesc -lLLVMBPFInfo -lLLVMAVRDisassembler -lLLVMAVRAsmParser -lLLVMAVRCodeGen -lLLVMAVRDesc -lLLVMAVRInfo -lLLVMARMDisassembler -lLLVMARMAsmParser -lLLVMARMCodeGen -lLLVMARMDesc -lLLVMARMUtils -lLLVMARMInfo -lLLVMAMDGPUTargetMCA -lLLVMAMDGPUDisassembler -lLLVMAMDGPUAsmParser -lLLVMAMDGPUCodeGen -lLLVMAMDGPUDesc -lLLVMAMDGPUUtils -lLLVMAMDGPUInfo -lLLVMAArch64Disassembler -lLLVMAArch64AsmParser -lLLVMAArch64CodeGen -lLLVMAArch64Desc -lLLVMAArch64Utils -lLLVMAArch64Info -lLLVMOrcJIT -lLLVMWindowsDriver -lLLVMMCJIT -lLLVMJITLink -lLLVMInterpreter -lLLVMExecutionEngine -lLLVMRuntimeDyld -lLLVMOrcTargetProcess -lLLVMOrcShared -lLLVMDWP -lLLVMDebugInfoLogicalView -lLLVMDebugInfoGSYM -lLLVMOption -lLLVMObjectYAML -lLLVMObjCopy -lLLVMMCA -lLLVMMCDisassembler -lLLVMLTO -lLLVMPasses -lLLVMCFGuard -lLLVMCoroutines -lLLVMipo -lLLVMVectorize -lLLVMLinker -lLLVMInstrumentation -lLLVMFrontendOpenMP -lLLVMFrontendOpenACC -lLLVMFrontendHLSL -lLLVMExtensions -lLLVMDWARFLinkerParallel -lLLVMDWARFLinker -lLLVMGlobalISel -lLLVMMIRParser -lLLVMAsmPrinter -lLLVMSelectionDAG -lLLVMCodeGen -lLLVMTarget -lLLVMObjCARCOpts -lLLVMCodeGenTypes -lLLVMIRPrinter -lLLVMInterfaceStub -lLLVMFileCheck -lLLVMFuzzMutate -lLLVMScalarOpts -lLLVMInstCombine -lLLVMAggressiveInstCombine -lLLVMTransformUtils -lLLVMBitWriter -lLLVMAnalysis -lLLVMProfileData -lLLVMSymbolize -lLLVMDebugInfoBTF -lLLVMDebugInfoPDB -lLLVMDebugInfoMSF -lLLVMDebugInfoDWARF -lLLVMObject -lLLVMTextAPI -lLLVMMCParser -lLLVMIRReader -lLLVMAsmParser -lLLVMMC -lLLVMDebugInfoCodeView -lLLVMBitReader -lLLVMFuzzerCLI -lLLVMCore -lLLVMRemarks -lLLVMBitstreamReader -lLLVMBinaryFormat -lLLVMTargetParser -lLLVMSupport -lLLVMDemangle -lz -lzstd -fno-sanitize-thread -OReleaseSafe --dep aro --dep aro_translate_c --dep build_options -Mroot=/Users/teampuzel/OpenSource/zig/src/main.zig -Maro=/Users/teampuzel/OpenSource/zig/lib/compiler/aro/aro.zig --dep aro -Maro_translate_c=/Users/teampuzel/OpenSource/zig/lib/compiler/aro_translate_c.zig -Mbuild_options=/Users/teampuzel/OpenSource/zig/zig-cache/c/2dc9068ab484fd5a686bcf3cc1a8f8f5/options.zig -lc++ -lc --cache-dir /Users/teampuzel/OpenSource/zig/zig-cache --global-cache-dir /Users/teampuzel/.cache/zig --name zig -L /Users/teampuzel/local/llvm17-release/lib -I /Users/teampuzel/local/llvm17-release/include -L /opt/homebrew/opt/zstd/lib -I /opt/homebrew/opt/zstd/include --zig-lib-dir /Users/teampuzel/OpenSource/zig/lib --listen=- 
Build Summary: 5/8 steps succeeded; 1 failed (disable with --summary none)
install transitive failure
└─ install zig transitive failure
   └─ zig build-exe zig ReleaseSafe native 5 errors
error: the following build command failed with exit code 1:
/Users/teampuzel/OpenSource/zig/zig-cache/o/1694726d7c52352d1f6a630ff604cc48/build /Users/teampuzel/Downloads/zig-macos-aarch64-0.12.0-dev.3518+d2be725e4/zig /Users/teampuzel/OpenSource/zig /Users/teampuzel/OpenSource/zig/zig-cache /Users/teampuzel/.cache/zig --seed 0xd0f7c164 -Zd69050eb6a06d25f -p stage3 --search-prefix /Users/teampuzel/local/llvm17-release --search-prefix /opt/homebrew/opt/zstd --zig-lib-dir lib -Dstatic-llvm -Dllvm-has-m68k -Doptimize=ReleaseSafe

[Vexu]

Your LLVM needs to also be built with -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD="M68k".

[TeamPuzel]

Yeah, I did build llvm with the experimental m68k target, like I said the clang I built does recognize the target.

[kassane]

build.zig bootstrap no add experimental targets libraries.

Similar issue: #5467 (comment)

[kassane]

My zig-fork with

    "LLVMM68kCodeGen",
    "LLVMM68kDesc",
    "LLVMM68kDisassembler",
    "LLVMM68kAsmParser",
    "LLVMM68kInfo",

$ cat start.c 
void _start(){}

$ zig cc -target m68k-freestanding-none start.c -c -v
clang version 18.0.0git
Target: m68k-unknown-unknown-unknown
Thread model: posix
InstalledDir: /usr/bin
 (in-process)
 "/home/kassane/zig-bootstrap/out/zig-mos-x86_64-linux-musl-baseline/zig" -cc1 -triple m68k-unknown-unknown-unknown -emit-obj -mrelax-all -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name start.c -mrelocation-model static -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -ffreestanding -debug-info-kind=constructor -dwarf-version=4 -debugger-tuning=gdb -gdwarf32 -fdebug-compilation-dir=/home/kassane/zig-bootstrap -v -fcoverage-compilation-dir=/home/kassane/zig-bootstrap -nostdsysteminc -nobuiltininc -resource-dir /home/kassane/zig-bootstrap/out/lib/clang/18 -dependency-file /home/kassane/.cache/zig/tmp/124d4dd3231e3be0-start.o.d -MT /home/kassane/.cache/zig/tmp/124d4dd3231e3be0-start.o -sys-header-deps -MV -isystem out/zig-mos-x86_64-linux-musl-baseline/lib/include -D _DEBUG -O0 -ferror-limit 19 -fsanitize=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,integer-divide-by-zero,nonnull-attribute,null,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound -fsanitize-trap=alignment,array-bounds,bool,builtin,enum,float-cast-overflow,integer-divide-by-zero,nonnull-attribute,null,pointer-overflow,return,returns-nonnull-attribute,shift-base,shift-exponent,signed-integer-overflow,unreachable,vla-bound -fno-sanitize-memory-param-retval -fno-sanitize-address-use-odr-indicator -fgnuc-version=4.2.1 -fcolor-diagnostics -fno-spell-checking -target-cpu generic -target-feature +isa-68000 -target-feature -isa-68010 -target-feature -isa-68020 -target-feature -isa-68030 -target-feature -isa-68040 -target-feature -isa-68060 -target-feature -isa-68881 -target-feature -isa-68882 -target-feature -reserve-a0 -target-feature -reserve-a1 -target-feature -reserve-a2 -target-feature -reserve-a3 -target-feature -reserve-a4 -target-feature -reserve-a5 -target-feature -reserve-a6 -target-feature -reserve-d0 -target-feature -reserve-d1 -target-feature -reserve-d2 -target-feature -reserve-d3 -target-feature -reserve-d4 -target-feature -reserve-d5 -target-feature -reserve-d6 -target-feature -reserve-d7 -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/kassane/.cache/zig/tmp/124d4dd3231e3be0-start.o -x c start.c
clang -cc1 version 18.0.0git based upon LLVM 18.0.0git default target x86_64-linux-musl
#include "..." search starts here:
#include <...> search starts here:
 out/zig-mos-x86_64-linux-musl-baseline/lib/include
End of search list.
LLD Link... ld.lld -r --error-limit=0 --image-base=65536 --eh-frame-hdr -znow -static -o start.o /home/kassane/.cache/zig/o/abd428bca8cfaa8d5f581a275cccb138/start.o --allow-shlib-undefined
Aborted (core dumped)

$ ./gcc-m68k/bin/m68k-elf-objdump -x $HOME/.cache/zig/o/abd428bca8cfaa8d5f581a275cccb138/start.o | head -n 5

/home/kassane/.cache/zig/o/abd428bca8cfaa8d5f581a275cccb138/start.o:     file format elf32-m68k
/home/kassane/.cache/zig/o/abd428bca8cfaa8d5f581a275cccb138/start.o
architecture: m68k, flags 0x00000011:
HAS_RELOC, HAS_SYMS

$ cat start.zig 
export fn _start() callconv(.C) void {
}

$ zig cc -target m68k-freestanding-none start.zig -c -v    
LLVM Emit Object... error(codegen): LLVM failed to parse 'm68k-unknown-unknown-unknown': Unable to find target for this triple (no targets are registered)
thread 114923 panic: Invalid LLVM triple
Unwind error at address `exe:0xa396134` (error.InvalidDebugInfo), trace may be incomplete

Aborted (core dumped)

Reference

• m68k backend is crashing with segfault #11132 (comment)
• Implement AsmParser and Disassembler for M68k llvm/llvm-project#48320

[alexrp]

Note that m68k support in LLVM and Clang is still highly experimental and missing lots of essential features. Realistically, don't expect support for this target to be usable for some years still.