Commit 530cc2c111

Andrew Kelley <andrew@ziglang.org>
2025-08-29 03:29:48
std.Io.Reader: work around llvm backend bug
tracked by #25067 and I already have a fix cooking in another branch
master
1 parent 46b60dc
Changed files (1)
lib
std
Io
Reader.zig
lib/std/Io/Reader.zig
@@ -1163,7 +1163,11 @@ pub inline fn takeStruct(r: *Reader, comptime T: type, endian: std.builtin.Endia
         .@"struct" => |info| switch (info.layout) {
             .auto => @compileError("ill-defined memory layout"),
             .@"extern" => {
-                var res = (try r.takeStructPointer(T)).*;
+                // This code works around https://github.com/ziglang/zig/issues/25067
+                // by avoiding a call to `peekStructPointer`.
+                const struct_bytes = try r.takeArray(@sizeOf(T));
+                var res: T = undefined;
+                @memcpy(@as([]u8, @ptrCast(&res)), struct_bytes);
                 if (native_endian != endian) std.mem.byteSwapAllFields(T, &res);
                 return res;
             },
@@ -1188,7 +1192,11 @@ pub inline fn peekStruct(r: *Reader, comptime T: type, endian: std.builtin.Endia
         .@"struct" => |info| switch (info.layout) {
             .auto => @compileError("ill-defined memory layout"),
             .@"extern" => {
-                var res = (try r.peekStructPointer(T)).*;
+                // This code works around https://github.com/ziglang/zig/issues/25067
+                // by avoiding a call to `peekStructPointer`.
+                const struct_bytes = try r.peekArray(@sizeOf(T));
+                var res: T = undefined;
+                @memcpy(@as([]u8, @ptrCast(&res)), struct_bytes);
                 if (native_endian != endian) std.mem.byteSwapAllFields(T, &res);
                 return res;
             },