diff --git a/CMakeLists.txt b/CMakeLists.txt
index c3fcf4ba..672e63bb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,7 +19,24 @@ function(add_compile_options_safe FLAG)
 endfunction()
 
 if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
-    add_compile_options(-Wall -Wextra -pedantic -Wcast-qual -Wfloat-equal -Wmissing-declarations -Wmissing-format-attribute -Wredundant-decls -Wshadow -Wundef -Wold-style-cast -Wno-multichar)
+    add_compile_options(-pedantic)
+    add_compile_options(-Wall)
+    add_compile_options(-Wextra)
+    add_compile_options(-Wcast-qual)                # Cast for removing type qualifiers
+    add_compile_options(-Wfloat-equal)              # Floating values used in equality comparisons
+    add_compile_options(-Wmissing-declarations)     # If a global function is defined without a previous declaration
+    add_compile_options(-Wmissing-format-attribute) #
+    add_compile_options(-Wno-long-long)
+    add_compile_options(-Wpacked)                   #
+    add_compile_options(-Wredundant-decls)          # if anything is declared more than once in the same scope
+    add_compile_options(-Wundef)
+    add_compile_options(-Wno-missing-braces)
+    add_compile_options(-Wno-sign-compare)
+    add_compile_options(-Wno-multichar)
+    add_compile_options(-Woverloaded-virtual)       # when a function declaration hides virtual functions from a base class
+
+    add_compile_options(-Wsuggest-attribute=noreturn)
+    add_compile_options_safe(-Wuseless-cast)
 elseif (CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
     add_compile_definitions(_CRT_SECURE_NO_WARNINGS)
 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
diff --git a/test.cpp b/test.cpp
index 187b7ec6..86e6ddc8 100644
--- a/test.cpp
+++ b/test.cpp
@@ -279,9 +279,9 @@ static void characterLiteral()
 
 #ifdef __GNUC__
     // BEGIN Implementation-specific results
-    ASSERT_EQUALS(static_cast<int>('AB'), simplecpp::characterLiteralToLL("'AB'"));
-    ASSERT_EQUALS(static_cast<int>('ABC'), simplecpp::characterLiteralToLL("'ABC'"));
-    ASSERT_EQUALS(static_cast<int>('ABCD'), simplecpp::characterLiteralToLL("'ABCD'"));
+    ASSERT_EQUALS('AB', simplecpp::characterLiteralToLL("'AB'"));
+    ASSERT_EQUALS('ABC', simplecpp::characterLiteralToLL("'ABC'"));
+    ASSERT_EQUALS('ABCD', simplecpp::characterLiteralToLL("'ABCD'"));
     ASSERT_EQUALS('\134t', simplecpp::characterLiteralToLL("'\\134t'")); // cppcheck ticket #7452
     // END Implementation-specific results
 #endif