Background

The test CMake build now supports a minimal default warning profile (-Wall) and an opt-in maximal profile (-DJLT_TESTS_MAX_WARNINGS=ON).

When maximal warnings are enabled, the build succeeds but produces a large warning surface in jlt headers/tests.

Goal

Incrementally reduce warning output under maximal warnings, and eventually make it practical to run with warnings-as-errors in CI for jlt-owned code.

Suggested approach

• Capture and categorize warnings by type/source (e.g. -Wfloat-equal, sign-conversion, old-style-cast, unused parameter)
• Prioritize warnings in jlt/ headers first, then tests
• Keep third-party/vendor code (e.g. CSparse) out of this cleanup scope
• Replace exact floating-point equality checks in tests with tolerant comparisons where appropriate
• Add targeted suppressions only when warnings are intentional and documented
• Add a CI job or optional workflow to exercise maximal warnings mode

Repro

From tests/build:

cmake .. -DJLT_TESTS_MAX_WARNINGS=ON
cmake --build .

(Optional strict mode):

cmake .. -DJLT_TESTS_MAX_WARNINGS=ON -DJLT_TESTS_WARNINGS_AS_ERRORS=ON

Notes

This issue is for tracking cleanup work over time; not intended as a one-shot refactor.