Make codegen better behaved on msvc / gcc

For some reason gcc assumes that static constexpr array can be modified and does not attempt to zero init the string, reading from the array instead. Having the buffer be initialized in the function instead via a consteval seems to yield proper results.
MSVC just straight up doesn't understand static initialization and attempts to initialize the static buffer on every function call. Microsoft never fails to disappoint.

Author: kiroma

trantor/net/InetAddress.cc

@@ -206,10 +206,10 @@ static void byteToChars(std::string::iterator& dst, unsigned char byte)
     ++dst;
 }
 
-static constexpr char stringInitBuffer[15]{};
 static std::string iptos(unsigned inet_addr)
 {
     // Initialize with a static buffer to force the constructor of string to get fully inlined
+    constexpr char stringInitBuffer[15]{};
     std::string out(stringInitBuffer, 15);
     std::string::iterator dst = out.begin();
     byteToChars(dst, inet_addr >> 0 & 0xff);