Problem
When user code has a compile error, default mcpp build output is noisy and confusing:
- Ninja progress lines such as
[1/9] OBJ obj/main.o are shown. - The generated command exposes long
env LD_LIBRARY_PATH=... prefixes. - The same ninja/compiler output can be printed twice.
The local reproduction and proposed implementation plan are documented in .agents/docs/2026-05-26-build-error-output-optimization-plan.md.
Scope
- Keep default build errors focused on compiler diagnostics.
- Preserve full details under
--verbose. - Move tool runtime environment handling out of visible ninja command lines.
- Add regression coverage for the default build-error output.
Problem
When user code has a compile error, default
mcpp buildoutput is noisy and confusing:[1/9] OBJ obj/main.oare shown.env LD_LIBRARY_PATH=...prefixes.The local reproduction and proposed implementation plan are documented in
.agents/docs/2026-05-26-build-error-output-optimization-plan.md.Scope
--verbose.