http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59475
Bug ID: 59475
Summary: gcc with flag -O1 fails to find template
specialization when there is default one.
Product: gcc
Version: 4.8.2
Status: UNCONFIRMED
Severity: major
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: akela1101 at gmail dot com
Different behaviour with -O1 and without.
In first case g++ doesn't see template instantiation in .cpp and uses default.
In second case it uses .cpp even without function declaration.
Tested on x86 gcc-4.8.2 and x64 gcc-4.7.2.
Example:
=== A.h ===
#ifndef A_H
#define A_H
template<typename T>
int foo(T) { return 10; }
struct A
{
int x;
};
//template<>
//int foo(A t);
#endif // A_H
=== A.cpp ===
#include "A.h"
template<>
int foo(A t) { return t.x; }
=== main.cpp ===
#include "A.h"
int main()
{
A a;
a.x = 5;
int b = 10;
if( foo(a) == foo(b) ) return 1;
return 0;
}
=======
Run script from attachment. Output must be:
$ ./run.sh
Without flags
0
With -O1
1
