CNA-BUG-057: RegisterAllBuiltInXnbReaders() documentation still calls the general EffectReader a known-unsupported placeholder

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

XnbBuiltInReaders.hpp says the function registers "the known-unsupported placeholder (the general EffectReader, XNB-32A)", but it registers the implemented EffectReader and the placeholder hook registers nothing.

Identifier

CNA-BUG-057

Category

Bug

Subsystem

Documentation & release tooling

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::Internal::Xnb::RegisterAllBuiltInXnbReaders() (doc comment in XnbBuiltInReaders.hpp)

Expected behaviour

The one call a game makes to register the built-in XNB readers documents what it registers: the implemented EffectReader (EffectContentTypeReader.cpp), which reads the bytecode length and bytes, constructs Graphics::Effect(device, bytes) and wraps failures in ContentLoadException; it is renderer-qualified, not a refusal. It does not imply .fx source, DXBC or MGFX support.

Actual behaviour at TARGET

The doc comment in XnbBuiltInReaders.hpp still lists "the known-unsupported placeholder (the general EffectReader, XNB-32A)". XnbBuiltInReaders.cpp calls RegisterEffectXnbReader(), and RegisterKnownUnsupportedXnbReaders() (KnownUnsupportedContentTypeReader.cpp) has an empty body whose comment says no built-in reader is in that category any more. The KnownUnsupportedContentTypeReader documentation was corrected; this comment was not, and it has been unchanged since the alpha.1 tag.

Source locations

• modules/content/include/CNA/Internal/Xnb/XnbBuiltInReaders.hpp — RegisterAllBuiltInXnbReaders doc comment
• modules/content/src/Xnb/XnbBuiltInReaders.cpp — RegisterAllBuiltInXnbReaders - registers the real EffectReader
• modules/content/src/Xnb/EffectContentTypeReader.cpp — EffectReader::Read
• modules/content/src/Xna/KnownUnsupportedContentTypeReader.cpp — RegisterKnownUnsupportedXnbReaders - empty

Evidence

Checked by reading at 009d40f5; not executed. Git history shows the comment identical at the alpha.1 tag and at 009d40f5, so an earlier conclusion that this was fixed (based on the implementation, registration and tests agreeing) missed this surviving comment. The site's XNB guide already describes the reader correctly ("EffectReader is renderer-qualified").

Focused reproduction

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

Current tests

XnbBuiltInReaderRegistrationTests.cpp asserts that Microsoft.Xna.Framework.Content.EffectReader is registered; no test can check a doc comment.

Regression test

None beyond the existing registration test: the fix is a comment edit.

Blast radius

Readers of the header, typically someone porting a game who has to decide whether compiled Effect .xnb assets can load. No run-time behaviour is affected.

Workaround

No workaround is known.