CNA-BUG-109: The engine layer's capability-name table has no IndirectDraw entry, although its comment says a missing capability fails to compile

CNA snapshot 009d40f5  ·  Known Issues › Current bugs  ·  source links pinned to 009d40f5

nameOfCapability in graphics-ext's RequireCapability.cpp names 18 of the 19 GraphicsCapability members and returns 'an unrecognised capability' for IndirectDraw; the switch has no default but a missing case is at most a compiler warning.

Identifier

CNA-BUG-109

Category

Bug

Subsystem

Graphics & renderers

Status

Open

Verified against

CNA 009d40f5 (009d40f5dd085c4e674d3479675fac84b12b3e0a)

Severity

Low (a triage suggestion, not a project priority)

Evidence basis

Source-verified: read at TARGET, not executed

Tests touching this area

Yes: see Current tests

Affected contract

CNA::Graphics::detail::nameOfCapability (refusal messages of the graphics-ext RequireCapability helpers)

Expected behaviour

The helper's own comment: "Listed exhaustively and with no default:, so a capability added later fails to compile here rather than reaching a log as an unnamed capability".

Actual behaviour at TARGET

RequireCapability.cpp lists 18 of the 19 members of CNA::GraphicsCapability (GraphicsCapability.hpp) and omits IndirectDraw, falling through to "an unrecognised capability". A missing enumerator in a switch without default does not fail compilation in C++ (only -Wswitch warns, and neither graphics-ext nor the root CMake enables it), so the safeguard the comment relies on does not exist. At 009d40f5 the indirect-draw users (StorageBuffer.cpp, GpuInstanceCuller.cpp) test the capability directly, so no current refusal prints the wrong name.

Source locations

• modules/graphics-ext/src/RequireCapability.cpp — nameOfCapability switch
• modules/graphics/include/CNA/GraphicsCapability.hpp — GraphicsCapability enumeration including IndirectDraw

Evidence

Checked by reading the named sources at 009d40f5; nothing was built or executed for this entry.

Independent re-verification: Checked by reading the named sources at 009d40f5; nothing was built or executed. RequireCapabilityTests.cpp does enumerate capabilities through nameOfCapability (EveryCapabilityHasItsOwnName asserts none maps to the fallback), but it iterates a hand-written list of 18 capabilities that also lacks IndirectDraw, so it cannot notice the missing name; the regression is to add IndirectDraw to both the switch and that list, or to derive the list from the enum.

Focused reproduction

No focused reproduction is known. Nothing has been invented here; the evidence above is what exists.

Current tests

No test enumerates GraphicsCapability through nameOfCapability.

Regression test

Add the case and a test that every enumerator maps to a name other than the fallback (or compile the file with -Werror=switch).

Blast radius

Future refusal messages for IndirectDraw; latent today.

Workaround

No workaround is known.