ICE: error: bitcast with types of different sizes

[matthiaskrgr]

#![allow(dead_code)]

#[repr(C)]
#[derive(Copy, Clone)]
pub struct Floats {
    a: f64,
    b: u8,
    c: f64,
}


mod rustrt {
    use super::{Floats};

    extern "C" {
        pub fn rust_dbg_abi_2(f: Floats) -> Floats;
    }
}

fn test2() {
    unsafe {
        let f = Floats { a: 1.234567890e-15_f64, b: 0b_1010_1010, c: 1.0987654321e-15_f64 };
        let ff = rustrt::rust_dbg_abi_2(f);
    }
}

pub fn main() {
    test2();
}

warning: unused variable: `ff`
  --> struct-return.rs:23:13
   |
23 |         let ff = rustrt::rust_dbg_abi_2(f);
   |             ^^ help: if this is intentional, prefix it with an underscore: `_ff`
   |
   = note: `#[warn(unused_variables)]` on by default

libgccjit.so: error: bitcast with types of different sizes
input expression (size: 64):
 <addr_expr 0x7fba6bc2c140
    type <pointer_type 0x7fba6bc2b540
        type <record_type 0x7fba6bc2b498  BLK
            size <integer_cst 0x7fba6c124120 constant 192>
            unit-size <integer_cst 0x7fba6c124150 constant 24>
            user align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7fba6bc28dc8 fields <field_decl 0x7fba6bc0ad10 field_0>
            pointer_to_this <pointer_type 0x7fba6bc2b540>>
        unsigned DI
        size <integer_cst 0x7fba6c118c90 constant 64>
        unit-size <integer_cst 0x7fba6c118ca8 constant 8>
        align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7fba6bc28d20>
    visited
    arg:0 <var_decl 0x7fba6bc275a0 stack_var_1 type <record_type 0x7fba6bc2b498 >
        addressable visited BLK (null):0:0 size <integer_cst 0x7fba6c124120 192> unit-size <integer_cst 0x7fba6c124150 24>
        align:64 warn_if_not_align:0 context <function_decl 0x7fba6bc1b500 _ZN13struct_return5test217h02d4cb3545bc47b6E>
        chain <var_decl 0x7fba6bc27510 stack_var_2 type <record_type 0x7fba6bc28e70 >
            addressable visited BLK (null):0:0 size <integer_cst 0x7fba6c124120 192> unit-size <integer_cst 0x7fba6c124150 24>
            align:64 warn_if_not_align:0 context <function_decl 0x7fba6bc1b500 _ZN13struct_return5test217h02d4cb3545bc47b6E> chain <var_decl 0x7fba6bc27480 stack_var_1>>>>
requested type (size: 192):
 <record_type 0x7fba6bc28dc8  BLK
    size <integer_cst 0x7fba6c124120 type <integer_type 0x7fba6c0ff0a8 bitsizetype> constant 192>
    unit-size <integer_cst 0x7fba6c124150 type <integer_type 0x7fba6c0ff000 sizetype> constant 24>
    align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7fba6bc28dc8
    fields <field_decl 0x7fba6bc0ad10 field_0
        type <array_type 0x7fba6bc13c78 type <integer_type 0x7fba6c0ffdc8 long int>
            BLK
            size <integer_cst 0x7fba6c118d08 constant 0>
            unit-size <integer_cst 0x7fba6c118cc0 constant 0>
            align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7fba6bc13c78 domain <integer_type 0x7fba6bc13bd0>>
        BLK (null):0:0 size <integer_cst 0x7fba6c118d08 0> unit-size <integer_cst 0x7fba6c118cc0 0>
        align:64 warn_if_not_align:0 offset_align 256 decl_not_flexarray: 0 offset <integer_cst 0x7fba6c118cc0 0> bit-offset <integer_cst 0x7fba6c118d08 0> context <record_type 0x7fba6bc28dc8 >
        chain <field_decl 0x7fba6bc0ada8 field_1 type <real_type 0x7fba6c121a80 double>
            DF (null):0:0
            size <integer_cst 0x7fba6c118c90 constant 64>
            unit-size <integer_cst 0x7fba6c118ca8 constant 8>
            align:64 warn_if_not_align:0 offset_align 256 decl_not_flexarray: 0 offset <integer_cst 0x7fba6c118cc0 0> bit-offset <integer_cst 0x7fba6c118d08 0> context <record_type 0x7fba6bc28dc8 > chain <field_decl 0x7fba6bc0ae40 field_2>>>
    pointer_to_this <pointer_type 0x7fba6bc28d20>>
error: linking with `cc` failed: exit status: 1
  |
  = note: LC_ALL="C" PATH="/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/bin:/home/matthias/.cargo/bin:/home/matthias/bin:/usr/local/bin:/home/matthias/.cargo/bin:/home/matthias/.local/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/home/matthias/.dotnet/tools:/usr/lib/jvm/default/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl:/usr/lib/rustup/bin:/var/lib/snapd/snap/bin" VSLANG="1033" "cc" "-m64" "/tmp/rustcIkYMfd/symbols.o" "struct-return.struct_return.a49734a482d16c59-cgu.0.rcgu.o" "struct-return.1ep5rirkgdd51ahb.rcgu.o" "-Wl,--as-needed" "-L" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-cb92768712601a78.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libobject-64fdea3f4b4483a9.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libmemchr-7131d4e480a39cf1.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libaddr2line-5b0b0d3b7d32a280.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libgimli-ecb3c4cbccea6ca3.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-21489f6fc83bcf9c.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd_detect-4235769adaec73dc.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-39978a3c90cbbb03.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-2bcf5035b2e8207a.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libminiz_oxide-1f4a77c098ecaa29.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libadler-d85c31e2a520cb57.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-af274bde543c4a19.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcfg_if-54f3ccd06893aed8.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-99aff24c233bd0c8.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-4a9ff6e26a937e19.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-1ab040c8d581c1d5.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-1be5ab1a73b8d3c1.rlib" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-eaa0474023498767.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "/home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "struct-return" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs"
  = note: /usr/bin/ld: cannot find struct-return.struct_return.a49734a482d16c59-cgu.0.rcgu.o: No such file or directory
          /usr/bin/ld: warning: alignment 8 of symbol `_RNvNtNtNtCsle4rNbiKmem_4core3num7dec2flt5table17POWER_OF_FIVE_128' in /home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-1be5ab1a73b8d3c1.rlib(core-1be5ab1a73b8d3c1.core.f73e5ae8f2233ce4-cgu.3.rcgu.o) is smaller than 32 in /home/matthias/vcs/github/rustc_codegen_gcc_attempt2/rustc_codegen_gcc/build_sysroot/sysroot/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-1be5ab1a73b8d3c1.rlib(core-1be5ab1a73b8d3c1.core.f73e5ae8f2233ce4-cgu.11.rcgu.o)
          collect2: error: ld returned 1 exit status