[clang] 7bc00ce - [clang-repl] Remove memory leak of ASTContext/TargetMachine.

[Sunho Kim via cfe-commits]

Author: Sunho Kim
Date: 2022-06-18T06:36:25+09:00
New Revision: 7bc00ce5cd41aad5fd0775f58c8e85a0a8d9ee56

URL: https://github.com/llvm/llvm-project/commit/7bc00ce5cd41aad5fd0775f58c8e85a0a8d9ee56
DIFF: https://github.com/llvm/llvm-project/commit/7bc00ce5cd41aad5fd0775f58c8e85a0a8d9ee56.diff

LOG: [clang-repl] Remove memory leak of ASTContext/TargetMachine.

Removes memory leak of ASTContext and TargetMachine. When DisableFree is turned on, it intentionally leaks these instances as they can be trivially deallocated. This patch turns this off and delete Parser instance early so that they will not reference dangling pargma headers.

Asan shouldn't detect these as leaks normally, since burypointer is called for them. But, every invocation of incremental parser createa an additional leak of TargetMachine. If there are many invocations within a single test case, we easily reach number of leaks exceeding kGraveYardMaxSize (which is 12) and leaks start to get reported by asan buildbots.

Reviewed By: v.g.vassilev

Differential Revision: https://reviews.llvm.org/D127991

Added: 
    

Modified: 
    clang/lib/Interpreter/IncrementalParser.cpp
    clang/lib/Interpreter/Interpreter.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Interpreter/IncrementalParser.cpp b/clang/lib/Interpreter/IncrementalParser.cpp
index 0f1ef3233a2a1..e5712303cbbb2 100644
--- a/clang/lib/Interpreter/IncrementalParser.cpp
+++ b/clang/lib/Interpreter/IncrementalParser.cpp
@@ -134,7 +134,10 @@ IncrementalParser::IncrementalParser(std::unique_ptr<CompilerInstance> Instance,
   P->Initialize();
 }
 
-IncrementalParser::~IncrementalParser() { Act->FinalizeAction(); }
+IncrementalParser::~IncrementalParser() {
+  P.reset();
+  Act->FinalizeAction();
+}
 
 llvm::Expected<PartialTranslationUnit &>
 IncrementalParser::ParseOrWrapTopLevelDecl() {

diff  --git a/clang/lib/Interpreter/Interpreter.cpp b/clang/lib/Interpreter/Interpreter.cpp
index 470c9c289a749..564b24efebdd0 100644
--- a/clang/lib/Interpreter/Interpreter.cpp
+++ b/clang/lib/Interpreter/Interpreter.cpp
@@ -116,6 +116,9 @@ CreateCI(const llvm::opt::ArgStringList &Argv) {
   // times, reusing the same AST.
   Clang->getCodeGenOpts().ClearASTBeforeBackend = false;
 
+  Clang->getFrontendOpts().DisableFree = false;
+  Clang->getCodeGenOpts().DisableFree = false;
+
   return std::move(Clang);
 }