Set minimum versions for gcc/clang

src/ripple/app/main/Main.cpp

@@ -760,15 +760,6 @@ int main (int argc, char** argv)
     ripple::sha512_deprecatedMSVCWorkaround();
 #endif
 
-#if defined(__GNUC__) && !defined(__clang__)
-    auto constexpr gccver = (__GNUC__ * 100 * 100) +
-                            (__GNUC_MINOR__ * 100) +
-                            __GNUC_PATCHLEVEL__;
-
-    static_assert (gccver >= 50100,
-        "GCC version 5.1.0 or later is required to compile rippled.");
-#endif
-
     atexit(&google::protobuf::ShutdownProtobufLibrary);
 
     auto const result (ripple::run (argc, argv));

src/ripple/basics/date.h

@@ -70,10 +70,6 @@
 #ifdef __GNUC__
 # pragma GCC diagnostic push
 # pragma GCC diagnostic ignored "-Wpedantic"
-# if __GNUC__ < 5
-   // GCC 4.9 Bug 61489 Wrong warning with -Wmissing-field-initializers
-#  pragma GCC diagnostic ignored "-Wmissing-field-initializers"
-# endif
 #endif
 
 namespace date