diff --git a/CMakeLists.txt b/CMakeLists.txt
index efdc0d96..f13fb3fb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,49 +19,50 @@ function(add_compile_options_safe FLAG)
     endif()
 endfunction()
 
-if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
     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")
+
+    # we are not interested in these
+    set_source_files_properties(test.cpp PROPERTIES COMPILE_FLAGS -Wno-multichar)
+elseif (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
     add_compile_definitions(_CRT_SECURE_NO_WARNINGS)
-    # TODO: bump warning level
-    #add_compile_options(/W4)  # Warning Level
-    # TODO: enable warning
+
+    add_compile_options(/W4)  # Warning Level
+
+    add_compile_options(/wd4127)  # warning C4127: conditional expression is constant
+    add_compile_options(/wd4244)  # warning C4244: 'x': conversion from 'int' to 'char', possible loss of data
     add_compile_options(/wd4267)  # warning C4267: '...': conversion from 'size_t' to 'unsigned int', possible loss of data
+    add_compile_options(/wd4706)  # warning C4706: assignment within conditional expression
 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     add_compile_options(-Weverything)
+
     # no need for c++98 compatibility
     add_compile_options(-Wno-c++98-compat-pedantic)
-    # these are not really fixable
+
+    # these are not really fixable until newer standards
     add_compile_options(-Wno-exit-time-destructors)
     add_compile_options(-Wno-global-constructors)
     add_compile_options(-Wno-weak-vtables)
     add_compile_options_safe(-Wno-unsafe-buffer-usage)
     add_compile_options_safe(-Wno-nrvo)
-    # we are not interested in these
-    add_compile_options(-Wno-multichar)
-    add_compile_options(-Wno-four-char-constants)
-    # ignore C++11-specific warning
-    add_compile_options(-Wno-suggest-override)
-    add_compile_options(-Wno-suggest-destructor-override)
+
     # contradicts -Wcovered-switch-default
     add_compile_options(-Wno-switch-default)
+
     # TODO: fix these?
     add_compile_options(-Wno-padded)
     add_compile_options(-Wno-sign-conversion)
@@ -69,6 +70,9 @@ elseif (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     add_compile_options(-Wno-shorten-64-to-32)
     add_compile_options(-Wno-shadow-field-in-constructor)
 
+    # we are not interested in these
+    set_source_files_properties(test.cpp PROPERTIES COMPILE_FLAGS "-Wno-multichar -Wno-four-char-constants")
+
     if (CMAKE_CXX_COMPILER_VERSION VERSION_EQUAL 14 OR CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 14)
         # TODO: verify this regression still exists in clang-15
         if (CMAKE_BUILD_TYPE STREQUAL "Release" OR CMAKE_BUILD_TYPE STREQUAL "RelWithDebInfo")
diff --git a/Makefile b/Makefile
index b6bc26da..b7b54597 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 all:	testrunner simplecpp
 
 CPPFLAGS ?=
-CXXFLAGS = -Wall -Wextra -pedantic -Wcast-qual -Wfloat-equal -Wmissing-declarations -Wmissing-format-attribute -Wredundant-decls -Wundef -Wno-multichar -Wold-style-cast -std=c++11 -g $(CXXOPTS)
+CXXFLAGS = -Wall -Wextra -pedantic -Wcast-qual -Wfloat-equal -Wmissing-declarations -Wmissing-format-attribute -Wpacked -Wredundant-decls -Wundef -Woverloaded-virtual -std=c++11 -g $(CXXOPTS)
 LDFLAGS = -g $(LDOPTS)
 
 # Define test source dir macro for compilation (preprocessor flags)
@@ -9,6 +9,7 @@ TEST_CPPFLAGS = -DSIMPLECPP_TEST_SOURCE_DIR=\"$(CURDIR)\"
 
 # Only test.o gets the define
 test.o: CPPFLAGS += $(TEST_CPPFLAGS)
+test.o: CXXFLAGS += -Wno-multichar
 
 %.o: %.cpp	simplecpp.h
 	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $<