| //@ add-core-stubs |
| //@ normalize-stderr: "(abi|pref|unadjusted_abi_align): Align\([1-8] bytes\)" -> "$1: $$SOME_ALIGN" |
| /*! |
| C doesn't have zero-sized types... except it does. |
| |
| Standard C doesn't, but some C compilers, like GCC, implement ZSTs as a compiler extension. |
| This historically has wound up interacting with processor-specific ABIs in fairly ad-hoc ways. |
| e.g. despite being "zero-sized", sometimes C compilers decide ZSTs consume registers. |
| |
| That means these two function signatures may not be compatible: |
| |
| ``` |
| extern "C" fn((), i32, i32); |
| extern "C" fn(i32, (), i32); |
| ``` |
| */ |
| |
| /* |
| * ZST IN "C" IS ZERO-SIZED |
| */ |
| |
| //@ revisions: aarch64-darwin |
| //@[aarch64-darwin] compile-flags: --target aarch64-apple-darwin |
| //@[aarch64-darwin] needs-llvm-components: aarch64 |
| |
| //@ revisions: x86_64-linux |
| //@[x86_64-linux] compile-flags: --target x86_64-unknown-linux-gnu |
| //@[x86_64-linux] needs-llvm-components: x86 |
| |
| |
| /* |
| * ZST IN "C" IS PASS-BY-POINTER |
| */ |
| |
| // according to the SRV4 ABI, an aggregate is always passed in registers, |
| // and it so happens the GCC extension for ZSTs considers them as structs. |
| //@ revisions: powerpc-linux |
| //@[powerpc-linux] compile-flags: --target powerpc-unknown-linux-gnu |
| //@[powerpc-linux] needs-llvm-components: powerpc |
| |
| //@ revisions: s390x-linux |
| //@[s390x-linux] compile-flags: --target s390x-unknown-linux-gnu |
| //@[s390x-linux] needs-llvm-components: systemz |
| |
| //@ revisions: sparc64-linux |
| //@[sparc64-linux] compile-flags: --target sparc64-unknown-linux-gnu |
| //@[sparc64-linux] needs-llvm-components: sparc |
| |
| // The Win64 ABI uses slightly different handling for power-of-2 sizes in the ABI, |
| // so GCC decided that ZSTs are pass-by-pointer, as `0.is_power_of_two() == false` |
| //@ revisions: x86_64-pc-windows-gnu |
| //@[x86_64-pc-windows-gnu] compile-flags: --target x86_64-pc-windows-gnu |
| //@[x86_64-pc-windows-gnu] needs-llvm-components: x86 |
| |
| |
| #![feature(no_core, rustc_attrs)] |
| #![no_core] |
| #![crate_type = "lib"] |
| |
| extern crate minicore; |
| use minicore::*; |
| |
| #[rustc_abi(debug)] |
| extern "C" fn pass_zst(_: ()) {} //~ ERROR: fn_abi |
