[Mlir-commits] [mlir] bcf6f64 - [mlir] Add workaround for false positive in -Wfree-nonheap-object

[Fangrui Song]

Author: Fangrui Song
Date: 2021-07-21T16:16:20-07:00
New Revision: bcf6f641acdbeb208ea07a9e8ded37cd5b796d26

URL: https://github.com/llvm/llvm-project/commit/bcf6f641acdbeb208ea07a9e8ded37cd5b796d26
DIFF: https://github.com/llvm/llvm-project/commit/bcf6f641acdbeb208ea07a9e8ded37cd5b796d26.diff

LOG: [mlir] Add workaround for false positive in -Wfree-nonheap-object

Restore 499571ea835daf786626a0db1e12f890b6cd8f8d
reverted by 0082764605cc0e7e0363a41ffa77d214c3157aa6.

A compiler slightly older than
"[clang][Sema] removes -Wfree-nonheap-object reference param false positive"
may report the false positive.
We need to retain the workaround a bit longer so that such compilers
can be used to compile MLIR in a warning-free way.

Added: 
    

Modified: 
    mlir/lib/IR/OperationSupport.cpp

Removed: 
    


################################################################################
diff  --git a/mlir/lib/IR/OperationSupport.cpp b/mlir/lib/IR/OperationSupport.cpp
index b1feab3a60a8..cfa130233171 100644
--- a/mlir/lib/IR/OperationSupport.cpp
+++ b/mlir/lib/IR/OperationSupport.cpp
@@ -237,7 +237,9 @@ detail::OperandStorage::~OperandStorage() {
   if (isDynamicStorage()) {
     TrailingOperandStorage &storage = getDynamicStorage();
     storage.~TrailingOperandStorage();
-    free(&storage);
+    // Work around -Wfree-nonheap-object false positive fixed by D102728.
+    auto *mem = &storage;
+    free(mem);
   } else {
     getInlineStorage().~TrailingOperandStorage();
   }
@@ -371,8 +373,11 @@ MutableArrayRef<OpOperand> detail::OperandStorage::resize(Operation *owner,
     new (&newOperands[numOperands]) OpOperand(owner);
 
   // If the current storage is also dynamic, free it.
-  if (isDynamicStorage())
-    free(&storage);
+  if (isDynamicStorage()) {
+    // Work around -Wfree-nonheap-object false positive fixed by D102728.
+    auto *mem = &storage;
+    free(mem);
+  }
 
   // Update the storage representation to use the new dynamic storage.
   dynamicStorage.setPointerAndInt(newStorage, true);