Add clang_free to libclang to free memory allocated in libclang.

One of the problems libclang tests has running under Windows is memory
allocated in libclang.dll but being freed in the test executable, possibly
by a different memory manager. This patch exposes a new export function,
clang_free(), used to free any allocated memory with the same libclang.dll
memory manager that allocated the memory.

http://reviews.llvm.org/D10949

Reviewed by Reid Kleckner, Douglas Gregor.

llvm-svn: 241789

4 files changed, 17 insertions, 4 deletions

diff --git a/clang/include/clang-c/BuildSystem.h b/clang/include/clang-c/BuildSystem.h
index 7aa0191..8d323a4 100644
--- a/clang/include/clang-c/BuildSystem.h
+++ b/clang/include/clang-c/BuildSystem.h
@@ -73,7 +73,7 @@ clang_VirtualFileOverlay_setCaseSensitivity(CXVirtualFileOverlay,
  *
  * \param options is reserved, always pass 0.
  * \param out_buffer_ptr pointer to receive the buffer pointer, which should be
- * disposed using \c free().
+ * disposed using \c clang_free().
  * \param out_buffer_size pointer to receive the buffer size.
  * \returns 0 for success, non-zero to indicate an error.
  */
@@ -83,6 +83,14 @@ clang_VirtualFileOverlay_writeToBuffer(CXVirtualFileOverlay, unsigned options,
                                        unsigned *out_buffer_size);
 
 /**
+ * \brief free memory allocated by libclang, such as the buffer returned by
+ * \c CXVirtualFileOverlay() or \c clang_ModuleMapDescriptor_writeToBuffer().
+ *
+ * \param buffer memory pointer to free.
+ */
+CINDEX_LINKAGE void clang_free(void *buffer);
+
+/**
  * \brief Dispose a \c CXVirtualFileOverlay object.
  */
 CINDEX_LINKAGE void clang_VirtualFileOverlay_dispose(CXVirtualFileOverlay);
@@ -122,7 +130,7 @@ clang_ModuleMapDescriptor_setUmbrellaHeader(CXModuleMapDescriptor,
  *
  * \param options is reserved, always pass 0.
  * \param out_buffer_ptr pointer to receive the buffer pointer, which should be
- * disposed using \c free().
+ * disposed using \c clang_free().
  * \param out_buffer_size pointer to receive the buffer size.
  * \returns 0 for success, non-zero to indicate an error.
  */
diff --git a/clang/tools/libclang/BuildSystem.cpp b/clang/tools/libclang/BuildSystem.cpp
index e9423c3..fe3db75 100644
--- a/clang/tools/libclang/BuildSystem.cpp
+++ b/clang/tools/libclang/BuildSystem.cpp
@@ -84,6 +84,10 @@ clang_VirtualFileOverlay_writeToBuffer(CXVirtualFileOverlay VFO, unsigned,
   return CXError_Success;
 }
 
+void clang_free(void *buffer) {
+  free(buffer);
+}
+
 void clang_VirtualFileOverlay_dispose(CXVirtualFileOverlay VFO) {
   delete unwrap(VFO);
 }
diff --git a/clang/tools/libclang/libclang.exports b/clang/tools/libclang/libclang.exports
index f78f998..f6a7175 100644
--- a/clang/tools/libclang/libclang.exports
+++ b/clang/tools/libclang/libclang.exports
@@ -132,6 +132,7 @@ clang_findIncludesInFileWithBlock
 clang_findReferencesInFile
 clang_findReferencesInFileWithBlock
 clang_formatDiagnostic
+clang_free
 clang_getArgType
 clang_getArrayElementType
 clang_getArraySize
diff --git a/clang/unittests/libclang/LibclangTest.cpp b/clang/unittests/libclang/LibclangTest.cpp
index e827ebc..becebf0 100644
--- a/clang/unittests/libclang/LibclangTest.cpp
+++ b/clang/unittests/libclang/LibclangTest.cpp
@@ -63,7 +63,7 @@ struct TestVFO {
       clang_VirtualFileOverlay_writeToBuffer(VFO, 0, &BufPtr, &BufSize);
       std::string BufStr(BufPtr, BufSize);
       EXPECT_STREQ(Contents, BufStr.c_str());
-      free(BufPtr);
+      clang_free(BufPtr);
     }
     clang_VirtualFileOverlay_dispose(VFO);
   }
@@ -345,7 +345,7 @@ TEST(libclang, ModuleMapDescriptor) {
   clang_ModuleMapDescriptor_writeToBuffer(MMD, 0, &BufPtr, &BufSize);
   std::string BufStr(BufPtr, BufSize);
   EXPECT_STREQ(Contents, BufStr.c_str());
-  free(BufPtr);
+  clang_free(BufPtr);
   clang_ModuleMapDescriptor_dispose(MMD);
 }