Linux: `@cImport` stdlib.h missing `_Float64` type in 0.16.0-dev.1262+be4eaed7c

[happystraw]

Zig Version

0.16.0-dev.1262+be4eaed7c

Steps to Reproduce and Observed Behavior

Environment

• Working version: 0.15.2
• Broken version: 0.16.0-dev.1262+be4eaed7c
• OS: 6.17.7-arch1-1 x86_64 GNU/Linux

Reproduction Code

const std = @import("std");
const c = @cImport({
    @cInclude("stdlib.h");
});

pub fn main() void {
    const a: c._Float64 = 123.0;
    std.debug.print("test: a={any}\n", .{a});
}

Error

$ anyzig 0.16.0-dev.1262+be4eaed7c build-exe main.zig -lc
anyzig: appdata '/home/happystraw/.local/share/anyzig'
anyzig: zig '0.16.0-dev.1262+be4eaed7c' already exists at '/home/happystraw/.cache/zig/p/N-V-__8AACSPoBQh7D0nqqtq72aWM7tvkTXBuFMu56bvRrUx'
main.zig:7:15: error: root source file struct 'cimport' has no member named '_Float64'
    const a: c._Float64 = 123.0;
             ~^~~~~~~~~
.cache/zig/o/14c3f02c1a8b00b17580be8fbb6e5028/cimport.zig:1:1: note: struct declared here
pub const __builtin = @import("std").zig.c_translation.builtins;
^~~
referenced by:
    callMain [inlined]: .cache/zig/p/N-V-__8AACSPoBQh7D0nqqtq72aWM7tvkTXBuFMu56bvRrUx/lib/std/start.zig:687:22
    callMainWithArgs [inlined]: .cache/zig/p/N-V-__8AACSPoBQh7D0nqqtq72aWM7tvkTXBuFMu56bvRrUx/lib/std/start.zig:656:20
    main: .cache/zig/p/N-V-__8AACSPoBQh7D0nqqtq72aWM7tvkTXBuFMu56bvRrUx/lib/std/start.zig:671:28
    1 reference(s) hidden; use '-freference-trace=4' to see all references

This code compiles fine in Zig 0.15.2 but fails in 0.16.0-dev due to missing _Float64 type.

Expected Behavior

The code should compile and run successfully, as it did in Zig 0.15.2.

[Vexu]

Fixed in #204