------- Comment #2 from dpirch at gmail dot com 2009-02-18 22:16 ------- extfunc cannot change the value of f, it would lead to undefined behavior.
"If an attempt is made to modify an object defined with a const-qualified type through use of an lvalue with non-const-qualified type, the behavior is undefined." (ISO/IEC 9899:TC3, 6.7.3) BTW, the function is actually inlined if f is declared as static const. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39234
