9420327ad7
In ecc7e6ce4, we tried to inspect the `LambdaScopeInfo` on stack to recover the instantiating lambda captures. However, there was a mismatch in how we compared the pattern declarations of lambdas: the constraint instantiation used a tailored `getPatternFunctionDecl()` which is localized in SemaLambda that finds the very primal template declaration of a lambda, while `FunctionDecl::getTemplateInstantiationPattern` finds the latest template pattern of a lambda. This difference causes issues when lambdas are nested, as we always want the primary template declaration. This corrects that by moving `Sema::addInstantiatedCapturesToScope` from SemaConcept to SemaLambda, allowing it to use the localized version of `getPatternFunctionDecl`. It is also worth exploring to coalesce the implementation of `getPatternFunctionDecl` with `FunctionDecl::getTemplateInstantiationPattern`. But I’m leaving that for the future, as I’d like to backport this fix (ecc7e6ce4 made the issue more visible in clang 20, sorry!), and changing Sema’s ABI would not be suitable in that regards. Hence, no release note. Fixes https://github.com/llvm/llvm-project/issues/133719 (cherry picked from commit dcc2182bce3d2ef0e0a991664c51b4b3bfcf7197)
C language Family Front-end
Welcome to Clang.
This is a compiler front-end for the C family of languages (C, C++ and Objective-C) which is built as part of the LLVM compiler infrastructure project.
Unlike many other compiler frontends, Clang is useful for a number of things beyond just compiling code: we intend for Clang to be host to a number of different source-level tools. One example of this is the Clang Static Analyzer.
If you're interested in more (including how to build Clang) it is best to read the relevant websites. Here are some pointers:
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Information on Clang: http://clang.llvm.org/
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Building and using Clang: http://clang.llvm.org/get_started.html
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Clang Static Analyzer: http://clang-analyzer.llvm.org/
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Information on the LLVM project: http://llvm.org/
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If you have questions or comments about Clang, a great place to discuss them is on the Clang forums:
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If you find a bug in Clang, please file it in the LLVM bug tracker: