Enable -Wtrampolines by default.


--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -611,7 +611,7 @@ 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/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -3766,6 +3766,8 @@ headers---for that, @option{-Wunknown-pragmas} must also be used.
 @opindex Wno-trampolines
  Warn about trampolines generated for pointers to nested functions.
  
+ In Gentoo, @option{-Wtrampolines} is enabled by default.
+ 
  A trampoline is a small piece of data or code that is created at run
  time on the stack when the address of a nested function is taken, and
  is used to call the nested function indirectly.  For some targets, it