Bug 21806 – Overload selection ignores slice

Consider: void main() { ubyte[16] arr; pragma(msg, typeof(arr[])); pragma(msg, typeof(arr[].bar)); arr[].bar.writeln; // 123 } char bar()(in ubyte[] arr) { return 'X'; } int bar(size_t N)(in ubyte[N] arr) { return 123; } Compilation output: ubyte[] int Should be: ubyte[] char

Up to 2.065.0: Success with output: ----- ubyte[] char -----

This compilation output is correct. https://dlang.org/spec/function.html#function-overloading Both functions have match level 3: match with qualifier conversion. That's because `in` makes the parameter `const`, so `ubyte[]` needs to be converted to `const(ubyte)[]`. Then partial ordering determines `const(ubyte)[16]` to be more specialized than `const(ubyte)[]`, so the fixed size version is chosen.

A slice is taken from argument, it is not original ubyte[16]. If i create temp variable à-la auto tmp = arr[]; bar(tmp); then correct overload is used

@BorisCarvajal created dlang/dmd pull request #12399 "Fix Issue 21806 - Overload selection ignores slice" fixing this issue: - Fix Issue 21806 - Overload selection ignores slice https://github.com/dlang/dmd/pull/12399

Note that using raw functions: char bar(ubyte[] array); int bar(ubyte[16] array); is also a regression: Up to 2.067.1: Success with output: ----- ubyte[] char ----- Since 2.068.2: Success with output: ----- ubyte[] int -----

dlang/dmd pull request #12399 "Fix Issue 21806 - Overload selection ignores slice" was merged into stable: - 9dabb8f03cdb4e4acacd12449fc5558708e8746a by Boris Carvajal: Fix Issue 21806 - Overload selection ignores slice https://github.com/dlang/dmd/pull/12399

dlang/dmd pull request #12431 "merge stable" was merged into master: - 5bba6357deac1ba8d5994ffeb5c526716e89a274 by Boris Carvajal: Fix Issue 21806 - Overload selection ignores slice https://github.com/dlang/dmd/pull/12431