Segmentation fault when incorrectly casting with @as

[christianm20358]

Zig Version

0.12.0-dev.1+a327d8b99

Steps to Reproduce and Observed Output

I had an issue where some tests were failing to compile with unclear results, and I believe the compiler is seg-faulting when it reaches the invalid code.

const std = @import("std");

pub fn main() !void {
    const vec: @Vector(2, f32) = .{3, 4};
    const splat_multiply = vec * @as(f32, @splat(2));

    try std.testing.expect(
        std.meta.eql(
            splat_multiply,
            @Vector(2, f32){ 6, 8}
        )
    );
}

Specifically:

@as(f32, @splat(2))

is the invalid code. It successfully compiles when replaced with:

@as(@Vector(2, f32))

Example of the output when using build.zig

zig build-exe zig-test Debug native: error: the following command terminated unexpectedly:
./zig build-exe ./zig-test/src/main.zig --cache-dir ./zig-cache --global-cache-dir ~/.cache/zig --name zig-test --listen=-
Build Summary: 0/5 steps succeeded; 1 failed (disable with --summary none)
run transitive failure
└─ run zig-test transitive failure
   ├─ zig build-exe zig-test Debug native failure
   └─ install transitive failure
      └─ install zig-test transitive failure
         └─ zig build-exe zig-test Debug native (reused)
error: the following build command failed with exit code 1:
./zig-cache/o/c54104b2e024a8fd48d0e197aa77b784/build ./zig-test ~/.cache/zig run

When compiling with zig run on Windows, the compilation fails silently.

Trying zig run on Debian was where I found it was a segment fault.

└─$ zig run src/main.zig
Segmentation fault

I have not been able to reproduce with any other invalid usages of @as() other than with Vectors. The code segfaults even when the std.testing.expect() function is commented out.

Expected Output

A compile error and stack trace including the location of the invalid cast.

[mlugg]

Duplicate of #16567; will be fixed by #16604