x86_64 libgccjit error when the C ABI passes an argument larger than 16 bytes #711
Description
This code causes libgccjit errors:
#[derive(Copy, Clone,Default)] #[repr(C)] struct Many3 { f0: u64, f1: u64, f2: u8, } extern "C" fn struct_in_3(_: Many3){} #[no_mangle] fn do_test() { struct_in_3(Many3::default()); }The repr(C) on the struct is not needed, but it sliences the imporper-ctype warning.
error:
libgccjit.so: error: : bitcast with types of different sizes input expression (size: 64): <addr_expr 0x7efdb68e95c0 type <pointer_type 0x7efdb68f29d8 type <array_type 0x7efdb68f2930 type <integer_type 0x7efdb68ecc78 signed char> BLK size <integer_cst 0x7efdb6b60690 constant 192> unit-size <integer_cst 0x7efdb6b606c0 constant 24> user align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7efdb68f2888 domain <integer_type 0x7efdb68f2738> pointer_to_this <pointer_type 0x7efdb68f29d8>> unsigned DI size <integer_cst 0x7efdb6b60228 constant 64> unit-size <integer_cst 0x7efdb6b60240 constant 8> align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7efdb68f2a80> visited arg:0 <var_decl 0x7efdb68f8000 stack_var_1 type <array_type 0x7efdb68f2930> addressable visited BLK (null):0:0 size <integer_cst 0x7efdb6b60690 192> unit-size <integer_cst 0x7efdb6b606c0 24> align:64 warn_if_not_align:0 context <function_decl 0x7efdb68f4200 do_test>>> requested type (size: 192): <record_type 0x7efdb68eca80 BLK size <integer_cst 0x7efdb6b60690 type <integer_type 0x7efdb6b4b690 bitsizetype> constant 192> unit-size <integer_cst 0x7efdb6b606c0 type <integer_type 0x7efdb6b4b5e8 sizetype> constant 24> user align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7efdb68eca80 fields <field_decl 0x7efdb68f15a0 field_0 type <array_type 0x7efdb68f2000 type <integer_type 0x7efdb68ece70 long int> BLK size <integer_cst 0x7efdb6b602a0 constant 0> unit-size <integer_cst 0x7efdb6b60258 constant 0> user align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type 0x7efdb68f20a8 domain <integer_type 0x7efdb68ec9d8>> BLK (null):0:0 size <integer_cst 0x7efdb6b602a0 0> unit-size <integer_cst 0x7efdb6b60258 0> user align:64 warn_if_not_align:0 offset_align 256 decl_not_flexarray: 0 offset <integer_cst 0x7efdb6b60258 0> bit-offset <integer_cst 0x7efdb6b602a0 0> context <record_type 0x7efdb68eca80 > chain <field_decl 0x7efdb68f1640 field_1 type <integer_type 0x7efdb68ec7e0 size_t> unsigned DI (null):0:0 size <integer_cst 0x7efdb6b60228 constant 64> unit-size <integer_cst 0x7efdb6b60240 constant 8> user align:64 warn_if_not_align:0 offset_align 256 decl_not_flexarray: 0 offset <integer_cst 0x7efdb6b60258 0> bit-offset <integer_cst 0x7efdb6b602a0 0> context <record_type 0x7efdb68eca80 > chain <field_decl 0x7efdb68f16e0 field_2>>> pointer_to_this <pointer_type 0x7efdb68f2690>> error: could not copy "/app/output.example.f9d5a4a502c358ed-cgu.0.rcgu.s" to "/app/output.s": No such file or directory (os error 2) error: aborting due to 1 previous error Compiler returned: 1 Since the bitcast input is 64 bits in size(pointer on x86_64), and the output has the same size as the structure in question, it looks like we are bitcasting the pointer to a structure instead of the structure itself.