Emit error for user-defined conversion operators in HLSL by Copilot · Pull Request #6 · damyanp/DirectXShaderCompiler

Copilot · 2026-02-21T00:26:02Z

Understand the issue: user-defined conversion operators (e.g., operator float4()) are silently ignored in HLSL instead of producing an error
Add a new diagnostic err_hlsl_unsupported_conversion_operator in DiagnosticSemaKinds.td
Add HLSL check in CheckConversionDeclarator in SemaDeclCXX.cpp to emit error when a conversion operator is defined
Create test file tools/clang/test/SemaHLSL/conversion-operator-errors.hlsl following existing patterns
Build and verify the fix works (all new + existing operator tests pass)
Update diagnostic message to "conversion operator overloading is not allowed" for consistency with err_hlsl_overloading_operator_disallowed
Add release note entry in docs/ReleaseNotes.md
Add template-dependent conversion operator test case

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…soft#5103) Add err_hlsl_unsupported_conversion_operator diagnostic and check in CheckConversionDeclarator to reject conversion operators in HLSL. Previously these were silently ignored, misleading users into thinking their cast operator overloads were being used. Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

…oad is not allowed' Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

damyanp · 2026-02-23T18:00:05Z

@copilot add a short one-line description of this change to ReleaseNotes.md

Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Copilot · 2026-02-23T18:01:22Z

@copilot add a short one-line description of this change to ReleaseNotes.md

Added in ca5ca4f7 under the "Other Changes" section of the Upcoming Release.

… for `vk::SampledTexture2D` type. (microsoft#8149) Part of microsoft#7979 ```hlsl TemplateType GatherRed(float2 Location, int2 Offset1, int2 Offset2, int2 Offset3, int2 Offset4, uint Status); TemplateType GatherGreen(float2 Location, int2 Offset1, int2 Offset2, int2 Offset3, int2 Offset4, uint Status); TemplateType GatherBlue(float2 Location, int2 Offset1, int2 Offset2, int2 Offset3, int2 Offset4, uint Status); TemplateType GatherAlpha(float2 Location, int2 Offset1, int2 Offset2, int2 Offset3, int2 Offset4, uint Status); TemplateType GatherCmp(float Location, float CompareValue, int2 Offset, uint Status); TemplateType GatherCmpRed(float Location, float CompareValue, int2 Offset1, int2 Offset2, int2 Offset3, int2 Offset4, uint Status); ``` GatherCmpGreen, GatherCmpBlue, GatherCmpAlpha, GatherRaw are not supported.

damyanp · 2026-03-11T00:59:02Z

+// This test verifies that dxcompiler generates an error when defining
+// a conversion operator (cast operator), which is not supported in HLSL.
+
+struct MyStruct {


Should there be a test for the template-dependent case?

Added a template-dependent test case (template<typename T> struct TemplateStruct { operator T() { ... } }) in 2fcaf368. The error is caught at parse time in CheckConversionDeclarator, so it fires even without template instantiation.

Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

This commit fixes 2 warnings showing on when building on MacOS: - CMP0135: setting which policy is applied on download freshness check - METAL_IRCONVERTER case not matching the FindPackage filename.

) Update `DxilStructAnnotation` to be aware of target types. Otherwise the annotation would declare a struct with a single LinAlg Matrix type as empty, leading to invalid codegen. Declaration names match the style of the surrounding code. Fixes microsoft#8279

Addresses outstanding cleanup requests from the initial LinAlg exec test PR --------- Co-authored-by: Damyan Pepper <damyanp@microsoft.com>

Updates the SPIR-V dependencies, and update an invalid test.

The experimental Cooperative Vector feature has been superseded by LinAlg. This change removes the code supporting the old feature. Fixes microsoft#8147 --------- Co-authored-by: Helena Kotas <hekotas@microsoft.com> Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

DxilCounters.cpp wasn't getting updated when HLSL_COPY_GENERATED_SOURCES was set. This change fixes that, and includes the updated DxilCounters.cpp. add_hlsl_hctgen now adds the file extension to the target it creates, which allows us to generate both DxilCounters.h and DxilCounters.cpp. --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Previous docs were....misleading at best. This change makes them more accurate.

…oft#8174) (microsoft#8177) PR microsoft#7799 added debug info for global variables across all inlined subprograms, creating O(subprograms x globals) debug instructions. This caused 2-3x slower compilation for shaders with many globals and deeply-inlined functions. Fix: Instead of collecting ALL subprograms for a function (walking every instruction), only collect subprograms from the alloca's actual users -- the instructions that reference the specific global variable. This preserves the debug info feature (globals visible in inlined scopes that use them) while eliminating work for unrelated scopes. The 'Lower static global into Alloca' pass is 3.8x faster on a stress test (41ms -> 11ms), and overall debug compilation is ~10% faster. Fixes microsoft#8174 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…103-tests # Conflicts: # docs/ReleaseNotes.md

Initial plan

21d7684

Copilot AI assigned Copilot and damyanp Feb 21, 2026

Copilot started work on behalf of damyanp February 21, 2026 00:26 View session

Copilot AI changed the title ~~[WIP] Fix issue 5103 and add tests for validation~~ Emit error for user-defined conversion operators in HLSL Feb 21, 2026

Copilot AI requested a review from damyanp February 21, 2026 00:58

Copilot finished work on behalf of damyanp February 21, 2026 00:58

damyanp requested changes Feb 21, 2026

View reviewed changes

Comment thread tools/clang/include/clang/Basic/DiagnosticSemaKinds.td Outdated

Copilot started work on behalf of damyanp February 21, 2026 01:44 View session

Update diagnostic message for consistency: 'conversion operator overl…

744ec43

…oad is not allowed' Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Copilot AI requested a review from damyanp February 21, 2026 02:04

Copilot finished work on behalf of damyanp February 21, 2026 02:04

Copilot started work on behalf of damyanp February 21, 2026 03:52 View session

Fix diagnostic message: 'conversion operator overloading is not allowed'

ce85b5c

Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Copilot finished work on behalf of damyanp February 21, 2026 04:12

damyanp approved these changes Feb 21, 2026

View reviewed changes

Copilot started work on behalf of damyanp February 23, 2026 18:00 View session

Add release note for conversion operator error

ca5ca4f

Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Copilot AI requested a review from damyanp February 23, 2026 18:01

Copilot finished work on behalf of damyanp February 23, 2026 18:01

Merge branch 'main' into copilot/fix-issue-5103-tests

6247898

damyanp requested changes Mar 11, 2026

View reviewed changes

Copilot started work on behalf of damyanp March 11, 2026 00:59 View session

Add template-dependent conversion operator test case

2fcaf36

Co-authored-by: damyanp <8118402+damyanp@users.noreply.github.com>

Copilot AI requested a review from damyanp March 11, 2026 01:19

Copilot finished work on behalf of damyanp March 11, 2026 01:19

Keenuts and others added 10 commits March 26, 2026 09:36

[NFC][CMAKE] Fix warning on MacOS build (microsoft#8166)

6ea7cf1

This commit fixes 2 warnings showing on when building on MacOS: - CMP0135: setting which policy is applied on download freshness check - METAL_IRCONVERTER case not matching the FindPackage filename.

[SM6.10][LinAlg][HLK] Small test cleanups (microsoft#8295)

b87d15d

Addresses outstanding cleanup requests from the initial LinAlg exec test PR --------- Co-authored-by: Damyan Pepper <damyanp@microsoft.com>

Update SPIR-V deps (microsoft#8304)

9b0463b

Updates the SPIR-V dependencies, and update an invalid test.

Update IDxcVersionInfo header docs to be more accurate (microsoft#8066)

cdbd4e6

Previous docs were....misleading at best. This change makes them more accurate.

Merge remote-tracking branch 'upstream/main' into copilot/fix-issue-5…

2e477af

…103-tests # Conflicts: # docs/ReleaseNotes.md

Add link to bug#, wrap text

ad52cbd

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Emit error for user-defined conversion operators in HLSL#6

Emit error for user-defined conversion operators in HLSL#6
Copilot wants to merge 17 commits intomainfrom
copilot/fix-issue-5103-tests

Copilot AI commented Feb 21, 2026 •

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Copilot AI commented Feb 21, 2026 •

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