LLVM 20 #22780
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LLVM 20 #22780
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This needs to be cherry-picked to master when we want to start testing the llvm20 branch on the CI machines.
See: * https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc/77319 * https://discourse.llvm.org/t/rfc-project-hand-in-hand-llvm-libc-libc-code-sharing/77701 We're dropping support for C++03 for Zig due to the first change; it would be insane to ship 1018 duplicate header files just for this outdated use case. As a result of the second change, I had to bring in a subset of the headers from llvm-libc since libc++ now depends on these. Hopefully we can continue to get away with not copying the entirety of llvm-libc.
LLVM is increasingly making use of this module flag when present.
This ABI bug was fixed in LLVM 20.
LLVM 20 started tail-calling it in some of our test cases, resulting in:
error: AndMyCarIsOutOfGas
/home/alexrp/Source/ziglang/zig-llvm20/repro.zig:2:5: 0x103ef9d in main (repro)
return error.TheSkyIsFalling;
^
/home/alexrp/Source/ziglang/zig-llvm20/repro.zig:6:5: 0x103efa5 in main (repro)
return error.AndMyCarIsOutOfGas;
^
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/start.zig:656:37: 0x103ee83 in posixCallMainAndExit (repro)
const result = root.main() catch |err| {
^
instead of the expected:
error: AndMyCarIsOutOfGas
/home/alexrp/Source/ziglang/zig-llvm20/repro.zig:2:5: 0x103f00d in main (repro)
return error.TheSkyIsFalling;
^
/home/alexrp/Source/ziglang/zig-llvm20/repro.zig:6:5: 0x103f015 in main (repro)
return error.AndMyCarIsOutOfGas;
^
/home/alexrp/Source/ziglang/zig-llvm20/repro.zig:11:9: 0x103f01d in main (repro)
try bar();
^
We can now run these tests as part of test-modules w/o -Dtest-slow-targets. Closes #21096.
…rectories` tests for mips64(el).
These started failing with LLVM 20 for unclear reasons:
test-std
└─ run test std-mips64-linux.4.19...6.13.4-gnuabi64.2.28-mips64r2-Debug-libc 2798/2878 passed, 2 failed, 78 skipped
error: 'posix.test.test.link with relative paths' failed: expected 2, found 0
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/testing.zig:103:17: 0x1d9e5bf in expectEqualInner__anon_47031 (test)
return error.TestExpectedEqual;
^
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/posix/test.zig:311:9: 0x3650f57 in test.link with relative paths (test)
try testing.expectEqual(@as(@typeof(nstat.nlink), 2), nstat.nlink);
^
error: 'posix.test.test.linkat with different directories' failed: expected 2, found 0
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/testing.zig:103:17: 0x1d9e5bf in expectEqualInner__anon_47031 (test)
return error.TestExpectedEqual;
^
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/posix/test.zig:355:9: 0x3653377 in test.linkat with different directories (test)
try testing.expectEqual(@as(@typeof(nstat.nlink), 2), nstat.nlink);
^
error: while executing test 'zig.system.darwin.macos.test.detect', the following test command failed:
qemu-mips64 -L /opt/glibc/mips64-linux-gnu-n64 /home/alexrp/Source/ziglang/zig-llvm20/.zig-cache/o/22a8c3762ea56ae3a674fa9ad15f6657/test --seed=0xa1dbb43c --cache-dir=/home/alexrp/Source/ziglang/zig-llvm20/.zig-cache --listen=-
test-std
└─ run test std-mips64-linux.4.19...6.13.4-gnuabi64.2.28-mips64r2-Debug-libc 2798/2878 passed, 1 failed, 79 skipped
error: 'posix.test.test.linkat with different directories' failed: expected 2, found 0
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/testing.zig:103:17: 0x1d9e22f in expectEqualInner__anon_47031 (test)
return error.TestExpectedEqual;
^
/home/alexrp/Source/ziglang/zig-llvm20/lib/std/posix/test.zig:356:9: 0x3650b47 in test.linkat with different directories (test)
try testing.expectEqual(@as(@typeof(nstat.nlink), 2), nstat.nlink);
^
error: while executing test 'zig.system.darwin.macos.test.detect', the following test command failed:
qemu-mips64 -L /opt/glibc/mips64-linux-gnu-n64 /home/alexrp/Source/ziglang/zig-llvm20/.zig-cache/o/22a8c3762ea56ae3a674fa9ad15f6657/test --seed=0xa1dbb43c --cache-dir=/home/alexrp/Source/ziglang/zig-llvm20/.zig-cache --listen=-
Unfortunately, neither GDB nor LLDB want to play nice with qemu-mips64(el) at
the moment, so I can't easily debug these failures.
llvm/llvm-project#129843 This will be fixed with LLVM 20.1.1, so revert this commit by then.
…mFloat(). llvm/llvm-project#130408 This will probably be fixed with LLVM 20.1.1, so revert this commit by then.
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Currently targeting LLVM 20.1.0, but aiming for LLVM 20.1.1 by the time this is merged.
Test suite status:
test-fmt: ✔️test-cases: ✔️test-translate-c: ✔️test-run-translated-c: ✔️test-behavior: ✔️test-c-import: ✔️test-compiler-rt: ✔️test-universal-libc: ✔️test-std: ✔️test-unit: ✔️test-compare-output: ✔️test-standalone: ✔️test-c-abi: ✔️test-link: ✔️test-stack-traces: ✔️test-cli: ✔️test-asm-link: ✔️test-debugger: ✔️test-incremental: ✔️Bugs filed upstream:
llvm::isUIntN(BitWidth, val) && "Value is not an N-bit unsigned value"when building musl formips64-linux-muslabi64with Clang 20.1.0-rc1 llvm/llvm-project#125954llvm::isUIntN(BitWidth, val) && "Value is not an N-bit unsigned value"when using@llvm.usub.with.overflowon Hexagon llvm/llvm-project#127296llvm::isUIntN(BitWidth, val) && "Value is not an N-bit unsigned value"forload volatilefrom hardcoded pointer onpowerpc-linux-musleabihfllvm/llvm-project#127298@llvm.ctpop.i128foraarch64_bellvm/llvm-project#129843ldexpimplementation forx86_fp80llvm/llvm-project#130408isFullyInternal()llvm/llvm-project#130541Closes #22014.