https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79548
Bug ID: 79548
Summary: missing -Wunused-variable on a typedef'd variable in a
function template
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: msebor at gcc dot gnu.org
Target Milestone: ---
GCC diagnoses the unused local variable in function f() below but misses the
unused variable in the explicitly instantiated template g():
$ cat u.C && gcc -S -Wall -Wextra -Wpedantic -Wunused u.C
void f ()
{
typedef int T;
T t; // warning, ok
}
template <class T>
void g ()
{
T t; // warning, ok
typedef T U;
U u; // no warning, bug
}
template void g<int>();
u.C: In function ‘void f()’:
u.C:4:5: warning: unused variable ‘t’ [-Wunused-variable]
T t; // warning, ok
^
u.C: In instantiation of ‘void g() [with T = int]’:
u.C:16:22: required from here
u.C:10:5: warning: unused variable ‘t’ [-Wunused-variable]
T t; // warning, ok
^
