I was writing some pretty basic stuff when suddenly my code stopped compiling with LDC on release mode.

I got the commit which introduced the problem: https://github.com/renatoathaydes/dzipper/commit/2f2cd6f2b00d36129a97446bec25e660baef3187

Basically, I started using the std.datetime.systime module.

With DMD, I can still compile with release mode:

▶ dub build -c exe -b release
    Starting Performing "release" build using /Users/renato/dlang/dmd-2.106.1/osx/bin/dmd for x86_64.
    Building console-colors 1.2.0: building configuration [library]
    Building dzipper ~main: building configuration [exe]
     Linking dzipper
(dmd-2.106.1)

But with LDC, I get this error:

▶ dub build -c exe -b release
    Starting Performing "release" build using /Users/renato/dlang/ldc-1.35.0/bin/ldc2 for x86_64.
  Up-to-date console-colors 1.2.0: target for configuration [library] is up to date.
    Building dzipper ~main: building configuration [exe]
Error: Instruction does not dominate all uses!
  %93 = getelementptr inbounds i8, i8* %4, i64 12
  %91 = bitcast i8* %93 to i32*
Instruction does not dominate all uses!
  %30 = getelementptr inbounds i8, i8* %4, i64 10
  %28 = bitcast i8* %30 to i32*

Error /Users/renato/dlang/ldc-1.35.0/bin/ldc2 failed with exit code 1.
(ldc-1.35.0)

Without -b release, it works.

On Tuesday, 9 January 2024 at 20:40:48 UTC, Renato wrote:

Hello Renato,
Please report the problem in our bugtracker here: https://github.com/ldc-developers/ldc/issues

It would greatly help us if you can minimize the problem to a small test case that reproduces the issue. You can use dustmite for that, or try manually (might take a long time).

Thanks!
Johan

On Tuesday, 9 January 2024 at 23:12:03 UTC, Johan wrote:

Done!

And thanks for telling me about Dustmite :) I did try to find a minimum example manually but couldn't, but Dustmite managed it in around 5 minutes. Awesome tool.