[clang] e8cc37e - [clang][deps] Disable app extensions during scanning (#200041)

[via cfe-commits]

Author: Jan Svoboda
Date: 2026-05-27T14:49:23-07:00
New Revision: e8cc37e60d04ea2e25f03fbeeb8de59f4e640448

URL: https://github.com/llvm/llvm-project/commit/e8cc37e60d04ea2e25f03fbeeb8de59f4e640448
DIFF: https://github.com/llvm/llvm-project/commit/e8cc37e60d04ea2e25f03fbeeb8de59f4e640448.diff

LOG: [clang][deps] Disable app extensions during scanning (#200041)

Application extension contributes to the context hash, but only affects
the availability attribute on declarations. Since it cannot affect
dependencies, disable it for the scan to reduce the number of scanning
PCM variants.

Added: 
    

Modified: 
    clang/lib/DependencyScanning/DependencyScannerImpl.cpp

Removed: 
    


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diff  --git a/clang/lib/DependencyScanning/DependencyScannerImpl.cpp b/clang/lib/DependencyScanning/DependencyScannerImpl.cpp
index 42f87adba84c9..712e84ebedaf9 100644
--- a/clang/lib/DependencyScanning/DependencyScannerImpl.cpp
+++ b/clang/lib/DependencyScanning/DependencyScannerImpl.cpp
@@ -450,6 +450,10 @@ std::shared_ptr<CompilerInvocation> dependencies::createScanCompilerInvocation(
       true;
   ScanInvocation->getHeaderSearchOpts().ModulesForceValidateUserHeaders = false;
 
+  // Application extension only affects the handling of availability attributes,
+  // which cannot change the dependencies.
+  ScanInvocation->getLangOpts().AppExt = false;
+
   // Ensure that the scanner does not create new dependency collectors,
   // and thus won't write out the extra '.d' files to disk.
   ScanInvocation->getDependencyOutputOpts() = {};