Commit be483dabc8
Changed files (2)
lib
std
lib/std/mem/Allocator.zig
@@ -311,12 +311,15 @@ pub fn resize(self: Allocator, allocation: anytype, new_len: usize) bool {
/// `allocation` may be an empty slice, in which case a new allocation is made.
///
/// `new_len` may be zero, in which case the allocation is freed.
+///
+/// If the allocation's elements' type is zero bytes sized, `allocation.len` is set to `new_len`.
pub fn remap(self: Allocator, allocation: anytype, new_len: usize) t: {
const Slice = @typeInfo(@TypeOf(allocation)).pointer;
break :t ?[]align(Slice.alignment) Slice.child;
} {
const Slice = @typeInfo(@TypeOf(allocation)).pointer;
const T = Slice.child;
+
const alignment = Slice.alignment;
if (new_len == 0) {
self.free(allocation);
@@ -325,6 +328,11 @@ pub fn remap(self: Allocator, allocation: anytype, new_len: usize) t: {
if (allocation.len == 0) {
return null;
}
+ if (@sizeOf(T) == 0) {
+ var new_memory = allocation;
+ new_memory.len = new_len;
+ return new_memory;
+ }
const old_memory = mem.sliceAsBytes(allocation);
// I would like to use saturating multiplication here, but LLVM cannot lower it
// on WebAssembly: https://github.com/ziglang/zig/issues/9660
lib/std/mem.zig
@@ -228,6 +228,18 @@ test "Allocator.resize" {
}
}
+test "Allocator alloc and remap with zero-bit type" {
+ var values = try testing.allocator.alloc(void, 10);
+ defer testing.allocator.free(values);
+
+ try testing.expectEqual(10, values.len);
+ const remaped = testing.allocator.remap(values, 200);
+ try testing.expect(remaped != null);
+
+ values = remaped.?;
+ try testing.expectEqual(200, values.len);
+}
+
/// Copy all of source into dest at position 0.
/// dest.len must be >= source.len.
/// If the slices overlap, dest.ptr must be <= src.ptr.