Merge pull request swiftlang#31263 from akyrtzi/5.3-linker-error-astcontext-parser-only-lib

[5.3][AST] Fix a linker error for the parser-only library build

Author: akyrtzi

lib/AST/ASTContext.cpp

@@ -475,14 +475,19 @@ struct ASTContext::Implementation {
   /// The IRGen specific SIL transforms that have been registered.
   SILTransformCtors IRGenSILPasses;
 
+#if !SWIFT_BUILD_ONLY_SYNTAXPARSERLIB
   /// The scratch context used to allocate intrinsic data on behalf of \c swift::IntrinsicInfo
   std::unique_ptr<llvm::LLVMContext> IntrinsicScratchContext;
+#endif
 };
 
 ASTContext::Implementation::Implementation()
     : IdentifierTable(Allocator),
-      TheSyntaxArena(new syntax::SyntaxArena()),
-      IntrinsicScratchContext(new llvm::LLVMContext()) {}
+      TheSyntaxArena(new syntax::SyntaxArena())
+#if !SWIFT_BUILD_ONLY_SYNTAXPARSERLIB
+      , IntrinsicScratchContext(new llvm::LLVMContext())
+#endif
+      {}
 ASTContext::Implementation::~Implementation() {
   for (auto &cleanup : Cleanups)
     cleanup();
@@ -4799,6 +4804,8 @@ AutoDiffDerivativeFunctionIdentifier *AutoDiffDerivativeFunctionIdentifier::get(
 }
 
 llvm::LLVMContext &ASTContext::getIntrinsicScratchContext() const {
+#if !SWIFT_BUILD_ONLY_SYNTAXPARSERLIB
   return *getImpl().IntrinsicScratchContext.get();
+#endif
 }