| author |  Matthew Lugg <mlugg@mlugg.co.uk> 2024-12-15 11:08:07+00:00 |
| committer | Matthew Lugg <mlugg@mlugg.co.uk> 2024-12-15 11:09:04+00:00 |
| log | 72ba7f7e98b8cd00787e2903641e752e15264522 |
| tree | 7ad2a593be813469b9ac72f8542acb00625d6273 |
| parent | b5d3db5fc6104f9af8ab7d3f5cf05a5d4f30f721 |
| signature |  Commit is signed but in an unrecognized format. |
Sema: disallow runtime stores to pointers with comptime-only element types
2 files changed, 58 insertions(+), 1 deletions(-)
src- test
- cases
- compile_errors
src/Sema.zig+16-1
| ... | ... | @@ -3628,6 +3628,10 @@ fn zirAllocExtended( |
| 3628 | 3628 | } |
| 3629 | 3629 | } |
| 3630 | 3630 | |
| 3631 | if (small.has_type and try var_ty.comptimeOnlySema(pt)) { | |
| 3632 | return sema.analyzeComptimeAlloc(block, var_ty, alignment); | |
| 3633 | } | |
| 3634 | ||
| 3631 | 3635 | if (small.has_type) { |
| 3632 | 3636 | if (!small.is_const) { |
| 3633 | 3637 | try sema.validateVarType(block, ty_src, var_ty, false); |
| ... | ... | @@ -4075,7 +4079,7 @@ fn zirAlloc(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air.I |
| 4075 | 4079 | const ty_src = block.src(.{ .node_offset_var_decl_ty = inst_data.src_node }); |
| 4076 | 4080 | |
| 4077 | 4081 | const var_ty = try sema.resolveType(block, ty_src, inst_data.operand); |
| 4078 | if (block.is_comptime) { | |
| 4082 | if (block.is_comptime or try var_ty.comptimeOnlySema(pt)) { | |
| 4079 | 4083 | return sema.analyzeComptimeAlloc(block, var_ty, .none); |
| 4080 | 4084 | } |
| 4081 | 4085 | if (sema.func_is_naked and try var_ty.hasRuntimeBitsSema(pt)) { |
| ... | ... | @@ -31938,6 +31942,17 @@ fn storePtr2( |
| 31938 | 31942 | } else break :rs ptr_src; |
| 31939 | 31943 | } else ptr_src; |
| 31940 | 31944 | |
| 31945 | // We're performing the store at runtime; as such, we need to make sure the pointee type | |
| 31946 | // is not comptime-only. We can hit this case with a `@ptrFromInt` pointer. | |
| 31947 | if (try elem_ty.comptimeOnlySema(pt)) { | |
| 31948 | return sema.failWithOwnedErrorMsg(block, msg: { | |
| 31949 | const msg = try sema.errMsg(src, "cannot store comptime-only type '{}' at runtime", .{elem_ty.fmt(pt)}); | |
| 31950 | errdefer msg.destroy(sema.gpa); | |
| 31951 | try sema.errNote(ptr_src, msg, "operation is runtime due to this pointer", .{}); | |
| 31952 | break :msg msg; | |
| 31953 | }); | |
| 31954 | } | |
| 31955 | ||
| 31941 | 31956 | // We do this after the possible comptime store above, for the case of field_ptr stores |
| 31942 | 31957 | // to unions because we want the comptime tag to be set, even if the field type is void. |
| 31943 | 31958 | if ((try sema.typeHasOnePossibleValue(elem_ty)) != null) { |
test/cases/compile_errors/store_comptime_only_type_to_runtime_pointer.zig created+42
| ... | ... | @@ -0,0 +1,42 @@ |
| 1 | export fn a() void { | |
| 2 | const p: *fn () void = @ptrFromInt(4); | |
| 3 | p.* = undefined; | |
| 4 | } | |
| 5 | ||
| 6 | export fn b(p: *anyopaque) void { | |
| 7 | p.* = undefined; | |
| 8 | } | |
| 9 | ||
| 10 | export fn c(p: *anyopaque, q: *anyopaque) void { | |
| 11 | p.* = q.*; | |
| 12 | } | |
| 13 | ||
| 14 | const Opaque = opaque {}; | |
| 15 | export fn d(p: *Opaque) void { | |
| 16 | p.* = undefined; | |
| 17 | } | |
| 18 | ||
| 19 | export fn e() void { | |
| 20 | const p: *comptime_int = @ptrFromInt(16); | |
| 21 | p.* = undefined; | |
| 22 | } | |
| 23 | ||
| 24 | export fn f() void { | |
| 25 | const p: **comptime_int = @ptrFromInt(16); // double pointer ('*comptime_int' is comptime-only) | |
| 26 | p.* = undefined; | |
| 27 | } | |
| 28 | ||
| 29 | // error | |
| 30 | // | |
| 31 | // :3:9: error: cannot store comptime-only type 'fn () void' at runtime | |
| 32 | // :3:6: note: operation is runtime due to this pointer | |
| 33 | // :7:11: error: expected type 'anyopaque', found '@TypeOf(undefined)' | |
| 34 | // :7:11: note: cannot coerce to 'anyopaque' | |
| 35 | // :11:12: error: cannot load opaque type 'anyopaque' | |
| 36 | // :16:11: error: expected type 'tmp.Opaque', found '@TypeOf(undefined)' | |
| 37 | // :16:11: note: cannot coerce to 'tmp.Opaque' | |
| 38 | // :14:16: note: opaque declared here | |
| 39 | // :21:9: error: cannot store comptime-only type 'comptime_int' at runtime | |
| 40 | // :21:6: note: operation is runtime due to this pointer | |
| 41 | // :26:9: error: cannot store comptime-only type '*comptime_int' at runtime | |
| 42 | // :26:6: note: operation is runtime due to this pointer |