diff --git a/Makefile b/Makefile
index e79abe1..d3e2d93 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,9 @@ PROTOCOL_VERSION?=104
 WIN_CC=x86_64-w64-mingw32-gcc
 WIN_CXX=x86_64-w64-mingw32-g++
 WIN_CFLAGS=-O3 #-g3 -fsanitize=address
-WIN_CXXFLAGS=-Wall -Wno-unknown-pragmas -std=c++17 -O3 -fno-tree-dce -fno-inline-small-functions -DPROTOCOL_VERSION=$(PROTOCOL_VERSION) #-g3 -fsanitize=address
+WIN_CXX_VANILLA_MINGW_OPT_DISABLES=-fno-tree-dce -fno-inline-small-functions
+WIN_CXX_OPT_DISABLES=-fno-tree-dce -fno-tree-fre -fno-tree-vrp -fno-ipa-sra
+WIN_CXXFLAGS=-Wall -Wno-unknown-pragmas -std=c++17 -O3 $(WIN_CXX_OPT_DISABLES) -DPROTOCOL_VERSION=$(PROTOCOL_VERSION) #-g3 -fsanitize=address
 WIN_LDFLAGS=-static -lws2_32 -lwsock32 #-g3 -fsanitize=address
 WIN_SERVER=bin/winfusion.exe
 
@@ -100,6 +102,10 @@ windows : CFLAGS=$(WIN_CFLAGS)
 windows : CXXFLAGS=$(WIN_CXXFLAGS)
 windows : LDFLAGS=$(WIN_LDFLAGS)
 windows : SERVER=$(WIN_SERVER)
+windows :
+ifneq ($(shell $(WIN_CXX) --version | head -1 | egrep -o [0-9]+ | tail -3 | head -1), 10)
+WIN_CXX_OPT_DISABLES=$(WIN_CXX_VANILLA_MINGW_OPT_DISABLES)
+endif
 
 .SUFFIX: .o .c .cpp .h .hpp
 
diff --git a/src/CNStructs.cpp b/src/CNStructs.cpp
index 2c4c7b5..6d889ea 100644
--- a/src/CNStructs.cpp
+++ b/src/CNStructs.cpp
@@ -5,16 +5,16 @@
 
 std::string U16toU8(char16_t* src) {
     try {
-        std::wstring_convert<std::codecvt_utf8_utf16<char16_t>,char16_t> convert; 
-        return convert.to_bytes(src);   
-    } catch(std::exception e) {
+        std::wstring_convert<std::codecvt_utf8_utf16<char16_t>,char16_t> convert;
+        return convert.to_bytes(src);
+    } catch(const std::exception& e) {
         return "";
     }
 }
 
 // returns number of char16_t that was written at des
 size_t U8toU16(std::string src, char16_t* des) {
-    std::wstring_convert<std::codecvt_utf8_utf16<char16_t>,char16_t> convert; 
+    std::wstring_convert<std::codecvt_utf8_utf16<char16_t>,char16_t> convert;
     std::u16string tmp = convert.from_bytes(src);
 
     // copy utf16 string to buffer