Suppress shadowing warnings

fmt/format.cc

@@ -58,6 +58,10 @@
 # define FMT_CATCH(x) if (false)
 #endif
 
+// Disable the warning about declaration shadowing because it affects too
+// many valid cases.
+#pragma GCC diagnostic ignored "-Wshadow"
+
 #ifdef _MSC_VER
 # pragma warning(push)
 # pragma warning(disable: 4127)  // conditional expression is constant