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/* Test for _Atomic in C11. Test of valid code. See c11-atomic-2.c
for more exhaustive tests of assignment cases. */
/* { dg-do compile } */
/* { dg-options "-std=c11 -pedantic-errors" } */
/* The use of _Atomic as a qualifier, and of _Atomic (type-name), give
the same type. */
extern _Atomic int a;
extern _Atomic (int) a;
extern int *_Atomic b;
extern _Atomic (int *) b;
extern void f (int [_Atomic]);
extern void f (int *_Atomic);
/* _Atomic may be applied to arbitrary types, with or without other
qualifiers, and assignments may be made as with non-atomic
types. Structure and union elements may be atomic. */
_Atomic int ai1, ai2;
int i1;
volatile _Atomic long double ald1;
const _Atomic long double ald2;
long double ld1;
_Atomic _Complex double acd1, acd2;
_Complex double d1;
_Atomic volatile _Bool ab1;
int *p;
int *_Atomic restrict ap;
struct s { char c[1000]; };
_Atomic struct s as1;
struct s s1;
struct t { _Atomic int i; };
_Atomic struct t at1;
_Atomic struct t *atp1;
struct t t1;
union u { char c[1000]; };
_Atomic union u au1;
union u u1;
union v { _Atomic int i; };
_Atomic union v av1;
union v v1;
void
func (_Atomic volatile long al1)
{
ai1 = ai2;
ai1 = i1;
i1 = ai2;
ai1 = ald2;
ald1 = d1;
ld1 = acd2;
acd1 += ab1;
acd2 /= ai1;
p = ap;
ap = p;
ab1 = p;
as1 = s1;
s1 = as1;
at1 = t1;
t1 = at1;
/* It's unclear whether the undefined behavior (6.5.2.3#5) for
accessing elements of atomic structures and unions is at
translation or execution time; presume here that it's at
execution time. */
t1.i = at1.i;
at1.i = t1.i;
atp1->i = t1.i;
au1 = u1;
u1 = au1;
av1 = v1;
v1 = av1;
v1.i = av1.i;
av1.i = v1.i;
/* _Atomic is valid on register variables, even if not particularly
useful. */
register _Atomic volatile int ra1 = 1, ra2 = 2;
ra1 = ra2;
ra2 = ra1;
/* And on parameters. */
al1 = ra1;
ra2 = al1;
}
/* A function may return an atomic type. */
_Atomic int
func2 (int i)
{
return i;
}
/* Casts may specify atomic type. */
int
func3 (int i)
{
return func2 ((_Atomic long) i);
}
/* The _Atomic void type is valid. */
_Atomic void *avp;
/* An array of atomic elements is valid (the elements being atomic,
not the array). */
_Atomic int aa[10];
int
func4 (void)
{
return aa[2];
}
/* Increment and decrement are valid for atomic types when they are
valid for non-atomic types. */
void
func5 (void)
{
ald1++;
ald1--;
++ald1;
--ald1;
ai1++;
ai1--;
++ai1;
--ai1;
ab1++;
ab1--;
++ab1;
--ab1;
ap++;
ap--;
++ap;
--ap;
}
/* Compound literals may have atomic type. */
_Atomic int *aiclp = &(_Atomic int) { 1 };
/* Test unary & and *. */
void
func6 (void)
{
int i = *aiclp;
_Atomic int *p = &ai2;
}
/* Casts to atomic type are valid (although the _Atomic has little
effect because the result is an rvalue). */
int i2 = (_Atomic int) 1.0;
/* For pointer subtraction and comparisons, _Atomic does not count as
a qualifier. Likewise for conditional expressions. */
_Atomic int *xaip1;
volatile _Atomic int *xaip2;
void *xvp1;
void
func7 (void)
{
int r;
r = xaip1 - xaip2;
r = xaip1 < xaip2;
r = xaip1 > xaip2;
r = xaip1 <= xaip2;
r = xaip1 >= xaip2;
r = xaip1 == xaip2;
r = xaip1 != xaip2;
r = xaip1 == xvp1;
r = xaip1 != xvp1;
r = xvp1 == xaip1;
r = xvp1 != xaip1;
r = xaip1 == 0;
r = ((void *) 0) == xaip2;
(void) (r ? xaip1 : xaip2);
(void) (r ? xvp1 : xaip2);
(void) (r ? xaip2 : xvp1);
(void) (r ? xaip1 : 0);
(void) (r ? 0 : xaip1);
/* The result of a conditional expression between a pointer to
qualified or unqualified (but not atomic) void, and a pointer to
an atomic type, is a pointer to appropriately qualified, not
atomic, void. As such, it is valid to use further in conditional
expressions with other pointer types. */
(void) (r ? xaip1 : (r ? xaip1 : xvp1));
}
/* Pointer += and -= integer is valid. */
void
func8 (void)
{
b += 1;
b -= 2ULL;
ap += 3;
}
/* Various other cases of simple assignment are valid (some already
tested above). */
void
func9 (void)
{
ap = 0;
ap = (void *) 0;
xvp1 = atp1;
atp1 = xvp1;
}
/* Test compatibility of function types in cases where _Atomic matches
(see c11-atomic-3.c for corresponding cases where it doesn't
match). */
void fc0a (int const);
void fc0a (int);
void fc0b (int _Atomic);
void fc0b (int _Atomic);
void fc1a (int);
void
fc1a (x)
volatile int x;
{
}
void fc1b (_Atomic int);
void
fc1b (x)
volatile _Atomic int x;
{
}
void
fc2a (x)
const int x;
{
}
void fc2a (int); /* { dg-warning "follows non-prototype" } */
void
fc2b (x)
_Atomic int x;
{
}
void fc2b (_Atomic int); /* { dg-warning "follows non-prototype" } */
void fc3a (int);
void
fc3a (x)
volatile short x;
{
}
void fc3b (_Atomic int);
void
fc3b (x)
_Atomic short x;
{
}
void
fc4a (x)
const short x;
{
}
void fc4a (int); /* { dg-warning "follows non-prototype" } */
void
fc4b (x)
_Atomic short x;
{
}
void fc4b (_Atomic int); /* { dg-warning "follows non-prototype" } */
/* Test cases involving C_MAYBE_CONST_EXPR work. */
void
func10 (_Atomic int *p)
{
p[0 / 0] = 1; /* { dg-warning "division by zero" } */
p[0 / 0] += 1; /* { dg-warning "division by zero" } */
*p = 0 / 0; /* { dg-warning "division by zero" } */
*p += 0 / 0; /* { dg-warning "division by zero" } */
}
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