https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110406
Bug ID: 110406 Summary: d: Wrong code-gen returning POD structs by value Product: gcc Version: 13.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: d Assignee: ibuclaw at gdcproject dot org Reporter: ibuclaw at gcc dot gnu.org Target Milestone: --- Since 13.1 (r13-1104?), structs have been set the wrong mode, causing them to return differently to equivalent static arrays. --- struct cpuid_abcd_t { uint eax; uint ebx; uint ecx; uint edx; }; cpuid_abcd_t cpuid_insn(const uint in_eax) { cpuid_abcd_t ret = void; asm { "cpuid" : "=a" ( ret.eax ), "=b" ( ret.ebx ), "=c" ( ret.ecx ), "=d" ( ret.edx ) : "a" ( in_eax ) : ;} return ret; } uint[4] cpuid_insn2(const uint in_eax) { uint[4] ret = void; asm { "cpuid" : "=a" ( ret[0] ), "=b" ( ret[1] ), "=c" ( ret[2] ), "=d" ( ret[3] ) : "a" ( in_eax ) : ;} return ret; } --- The first function erroneously being returned in vector registers. _15 = {ret$eax_3, ret$ebx_4, ret$ecx_5, ret$edx_6}; MEM <vector(4) uint> [(void *)&D.1894] = _15; return D.1894;