Enable -Wtrampolines by default.


--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -648,7 +648,7 @@ Common Var(warn_system_headers) Warning
 Do not suppress warnings from system headers
 
 Wtrampolines
-Common Var(warn_trampolines) Warning
+Common Var(warn_trampolines) Init(1) Warning
 Warn whenever a trampoline is generated
 
 Wtype-limits
--- a/gcc/doc/gcc.info
+++ b/gcc/doc/gcc.info
@@ -4021,6 +4021,8 @@ compiler warns that an unrecognized option is present.
      and thus requires the stack to be made executable in order for the
      program to work properly.
 
+     This warning is enabled by default in Gentoo.
+
 '-Wfloat-equal'
      Warn if floating-point values are used in equality comparisons.