https://github.com/toddr/IO-Tty/pull/28

Index: Makefile.PL
--- Makefile.PL.orig
+++ Makefile.PL
@@ -15,7 +15,7 @@ use Config qw(%Config);
 
 my %cfg;
 @cfg{qw(cc ccflags ldflags)} = @Config{qw(cc ccflags ldflags)};
-for my $arg (@ARGV) {
+for (@ARGV) {
   if ( /^(CC|CCFLAGS|LDFLAGS)=(.*)/i ) {
     $cfg{lc($1)} = $2;
   }
