srctree

garrison hinson-hasty parent 7d41a5cb 1e67f502
Sema: fix compiler crash `@ptrCast`ing optional slice
inlinesplit
src/Sema.zig added: 59, removed: 3, total 56
@@ -22779,7 +22779,11 @@ fn ptrCastFull(
}
 
const ptr = if (src_info.flags.size == .Slice and dest_info.flags.size != .Slice) ptr: {
break :ptr try sema.analyzeSlicePtr(block, operand_src, operand, operand_ty);
if (operand_ty.zigTypeTag(mod) == .Optional) {
break :ptr try sema.analyzeOptionalSlicePtr(block, operand_src, operand, operand_ty);
} else {
break :ptr try sema.analyzeSlicePtr(block, operand_src, operand, operand_ty);
}
} else operand;
 
const dest_ptr_ty = if (dest_info.flags.size == .Slice and src_info.flags.size != .Slice) blk: {
@@ -32564,6 +32568,32 @@ fn analyzeSlicePtr(
return block.addTyOp(.slice_ptr, result_ty, slice);
}
 
fn analyzeOptionalSlicePtr(
sema: *Sema,
block: *Block,
opt_slice_src: LazySrcLoc,
opt_slice: Air.Inst.Ref,
opt_slice_ty: Type,
) CompileError!Air.Inst.Ref {
const mod = sema.mod;
const result_ty = opt_slice_ty.optionalChild(mod).slicePtrFieldType(mod);
 
if (try sema.resolveValue(opt_slice)) |opt_val| {
if (opt_val.isUndef(mod)) return mod.undefRef(result_ty);
const slice_ptr: InternPool.Index = if (opt_val.optionalValue(mod)) |val|
val.slicePtr(mod).toIntern()
else
.null_value;
 
return Air.internedToRef(slice_ptr);
}
 
try sema.requireRuntimeBlock(block, opt_slice_src, null);
 
const slice = try block.addTyOp(.optional_payload, opt_slice_ty, opt_slice);
return block.addTyOp(.slice_ptr, result_ty, slice);
}
 
fn analyzeSliceLen(
sema: *Sema,
block: *Block,
 
test/behavior/cast.zig added: 59, removed: 3, total 56
@@ -1550,6 +1550,32 @@ test "optional pointer coerced to optional allowzero pointer" {
try expect(@intFromPtr(q.?) == 4);
}
 
test "optional slice coerced to allowzero many pointer" {
const a: ?[]const u32 = null;
const b: [*]allowzero const u8 = @ptrCast(a);
const c = @intFromPtr(b);
try std.testing.expect(c == 0);
}
 
test "optional slice passed as parameter coerced to allowzero many pointer" {
const ns = struct {
const Color = struct {
r: u8,
g: u8,
b: u8,
a: u8,
};
 
fn foo(pixels: ?[]const Color) !void {
const data: [*]allowzero const u8 = @ptrCast(pixels);
const int = @intFromPtr(data);
try std.testing.expect(int == 0);
}
};
 
try ns.foo(null);
}
 
test "single item pointer to pointer to array to slice" {
var x: i32 = 1234;
try expect(@as([]const i32, @as(*[1]i32, &x))[0] == 1234);