Reject auto combined with type specifiers in C++ - #208552
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This commit fixes several issues related to 'auto' type specifier handling.
Core implementation:
- Add ConflictingTypeSpecifier flag to DeclSpec to track when 'auto' conflicts
with another type specifier (e.g., 'auto int' or 'int auto'). This allows
Finish() to properly handle the conflict based on language mode rather than
immediately emitting an error during parsing.
1. Fix 'auto auto' duplicate detection: Keep TypeSpecType as TST_auto after
emitting error so subsequent checks can emit function-specific errors
(e.g., 'not allowed in function prototype').
2. Fix OpenCL 'auto' and 'register' storage class errors: Reorder checks to
prioritize OpenCL-specific handling before C++11+ checks. Use
SetStorageClassSpec to trigger OpenCL validation and emit version-specific
error messages.
3. Fix C23 'int auto' and 'constexpr int auto' handling:
- For 'constexpr int auto': Treat 'auto' as type specifier conflict (don't
convert to storage class), emit single error message.
- For 'int auto' without constexpr: Convert 'auto' to storage class specifier
(no type conflict error), only emit 'illegal storage class' if applicable.
4. Fix template parameter parsing: Skip type name lookup when 'auto' is set
in template parameter context to avoid false ambiguity errors for
placeholder variables.
5. Fix concept constraint syntax: Detect 'C<T> auto' pattern and skip type
conflict detection for concept constraints.
6. Update test expectations: Align error messages and line numbers with
actual diagnostic locations and behavior.
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
to268
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Can you make PR title and description more... descriptive?
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
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Done. |
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Changes to C++ DR tests LGTM
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The regression fix LGTM.
I will try to reland the PR probably this weekend.
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The PR looks like to have passed post CI checks (I have merged the PR when the buildbot was offline this morning). |
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Follow-up of llvm#166004 - Diagnose C++ declarations that combine `auto` with another type specifier, such as `auto int` . - Preserve C/C23 handling where `auto` can still be interpreted as a storage-class specifier in valid combinations. - Fix parser disambiguation so `auto Use = 0` treats `Use` as the declarator name before type lookup, avoiding ambiguous lookup regressions. --------- Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
vangthao95
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) The PR #208552 has introduced a regression where brace initialization was not taken into account `auto foo{12}`. It was also breaking `dcl.type.general` p2 rules, which is also now tested.
dyung
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…#210347) The PR llvm#208552 has introduced a regression where brace initialization was not taken into account `auto foo{12}`. It was also breaking `dcl.type.general` p2 rules, which is also now tested. (cherry picked from commit d592aa5)
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This reverts commit 72af746.
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This reverts commit 72af746.
to268
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This reverts commit 72af746.
to268
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This reverts commit 25a419f.
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This reverts commit 72af746.
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…8552)" and follow-ups commits (#215320) The initial fix for #164273 had several follow up commits to fix the initial implementation. This fix induces a lot of regressions and a refactoring of the area is required in order to fix the issue in a later release. This reverts the following commits (from oldest to latest): 72af746 226acaf d592aa5 34436db de4b1f5
hulxv
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…8552)" and follow-ups commits (#215320) The initial fix for #164273 had several follow up commits to fix the initial implementation. This fix induces a lot of regressions and a refactoring of the area is required in order to fix the issue in a later release. This reverts the following commits (from oldest to latest): 72af746 226acaf d592aa5 34436db de4b1f5
dyung
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…m#208552)" and follow-ups commits (llvm#215320) The initial fix for llvm#164273 had several follow up commits to fix the initial implementation. This fix induces a lot of regressions and a refactoring of the area is required in order to fix the issue in a later release. This reverts the following commits (from oldest to latest): 72af746 226acaf d592aa5 34436db de4b1f5
zhangweize9-cyber
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…m#208552)" and follow-ups commits (llvm#215320) The initial fix for llvm#164273 had several follow up commits to fix the initial implementation. This fix induces a lot of regressions and a refactoring of the area is required in order to fix the issue in a later release. This reverts the following commits (from oldest to latest): 72af746 226acaf d592aa5 34436db de4b1f5
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Follow-up of #166004
autowith another type specifier, such asauto int.autocan still be interpreted as a storage-class specifier in valid combinations.auto Use = 0treatsUseas the declarator name before type lookup, avoiding ambiguous lookup regressions.