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// { dg-additional-options -Wparentheses }
// Most Vexing Parse warnings
// in C++ anythig that syntactically looks like a decl IS a decl, this
// can lead to confused users, but worse silent unexpectedly unsafe
// code generation.
int (a); // { dg-warning "" }
int (*b); // { dg-warning "" }
extern int (&c); // { dg-warning "" }
int h1 = 0, h2 = 0;
struct H { H(...);};
namespace fns
{
int (*a) ();
int (b) ();
int (*c ()) ();
int (d1 ()); // { dg-warning "" }
int (d2 // { dg-warning "" }
());
int (e) (int);
int g (int (a)); // No warning because ...
H h (int (h1), int (h2), 3); // ... not a function decl.
}
namespace arys
{
int (*a)[1];
int (b)[1];
int (*c[1])[1];
int (d1[1]); // { dg-warning "" }
int (d2
[1]);
int (e[1])[1];
}
namespace complex
{
int (*a())[1];
int (*b[1])();
int ((*c1())[1]); // { dg-warning "" }
int ((*c2())
[1]);
int ((*d1[1])()); // { dg-warning "" }
int ((*d2[1]) // { dg-warning "" }
());
}
namespace motivation
{
typedef int shared_mutex; // for exposition
struct locker
{
locker ();
locker (int &r);
~locker ();
};
class protected_state
{
shared_mutex mutex; // not a real mutex type
int state;
public:
void not_thread_safe ()
{
locker (mutex); // { dg-warning "" }
state++; // oops
}
void thread_safe ()
{
locker lock (mutex);
state++; // ok;
}
};
}
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