[lldb] Use llvm::format in AppleObjCRuntimeV2.cpp

Crushing a "sprintf" buffer is null warning.

diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
index 9bdbef3..750b6ce 100644 (file)
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
@@ -1625,19 +1625,13 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapSharedCache() {
     // Substitute in the correct class_getName / class_getNameRaw function name,
     // concatenate the two parts of our expression text.  The format string
     // has two %s's, so provide the name twice.
-    int prefix_string_size = snprintf (nullptr, 0, 
+    std::string shared_class_expression;
+    llvm::raw_string_ostream(shared_class_expression) << llvm::format(
                                g_shared_cache_class_name_funcptr,
                                class_name_getter_function_name.AsCString(),
                                class_name_getter_function_name.AsCString());
 
-    char *class_name_func_ptr_expr = (char*) malloc (prefix_string_size + 1);
-    snprintf (class_name_func_ptr_expr, prefix_string_size + 1,
-              g_shared_cache_class_name_funcptr,
-              class_name_getter_function_name.AsCString(),
-              class_name_getter_function_name.AsCString());
-    std::string shared_class_expression = class_name_func_ptr_expr;
     shared_class_expression += g_get_shared_cache_class_info_body;
-    free (class_name_func_ptr_expr);
 
     m_get_shared_cache_class_info_code.reset(
         GetTargetRef().GetUtilityFunctionForLanguage(