diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9fcd2806631..72ec22970d4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,7 +7,7 @@ SET(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}/bin")
 
 SET(CMAKE_CXX_FLAGS "-std=c++11 ${CMAKE_CXX_FLAGS}")
 SET(CMAKE_CXX_FLAGS "-msse2 -mfpmath=sse ${CMAKE_CXX_FLAGS}")
-SET(CMAKE_CXX_FLAGS "-O2 -Wall ${CMAKE_CXX_FLAGS}")
+SET(CMAKE_CXX_FLAGS "-O2 ${CMAKE_CXX_FLAGS}")
 
 # clang doesn't print colored diagnostics when invoked from Ninja
 IF (UNIX AND
diff --git a/src/pass.cpp b/src/pass.cpp
index 63b1a786984..59f51df09e9 100644
--- a/src/pass.cpp
+++ b/src/pass.cpp
@@ -86,7 +86,7 @@ P* PassRunner::getLast() {
 
 PassRunner::~PassRunner() {
   for (auto pass : passes) {
-    delete(pass);
+    delete pass;
   }
 }
 
diff --git a/src/wasm.h b/src/wasm.h
index 8583f949258..9571c0e7ed4 100644
--- a/src/wasm.h
+++ b/src/wasm.h
@@ -1107,6 +1107,7 @@ class Module {
 
 template<class ReturnType>
 struct WasmVisitor {
+  virtual ~WasmVisitor() {}
   // should be pure virtual, but https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51048
   // Expression visitors
   virtual ReturnType visitBlock(Block *curr) { abort(); }