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// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -std=c++11 -Wuninitialized -verify %s
// test1: Expect no diagnostics
int test1(int x) {
int y;
asm goto("nop" : "=r"(y) : "r"(x) : : err);
return y;
err:
return -1;
}
int test2(int x) {
int y; // expected-warning {{variable 'y' is used uninitialized whenever its declaration is reached}} \
// expected-note {{initialize the variable}}
if (x < 42)
asm volatile goto("testl %0, %0; testl %1, %2; jne %l3" : "+S"(x), "+D"(y) : "r"(x) :: indirect_1, indirect_2);
else
asm volatile goto("testl %0, %1; testl %2, %3; jne %l5" : "+S"(x), "+D"(y) : "r"(x), "r"(y) :: indirect_1, indirect_2);
return x + y;
indirect_1:
return -42;
indirect_2:
return y; // expected-note {{uninitialized use occurs here}}
}
int test3(int x) {
int y; // expected-warning {{variable 'y' is used uninitialized whenever its declaration is reached}} \
// expected-note {{initialize the variable}}
asm goto("xorl %1, %0; jmp %l2" : "=&r"(y) : "r"(x) : : fail);
normal:
y += x;
return y;
if (x) {
fail:
return y; // expected-note {{uninitialized use occurs here}}
}
return 0;
}
int test4(int x) {
int y; // expected-warning {{variable 'y' is used uninitialized whenever its declaration is reached}} \
// expected-note {{initialize the variable}}
goto forward;
backward:
return y; // expected-note {{uninitialized use occurs here}}
forward:
asm goto("# %0 %1 %2" : "=r"(y) : "r"(x) : : backward);
return y;
}
// test5: Expect no diagnostics
int test5(int x) {
int y;
asm volatile goto("testl %0, %0; testl %1, %2; jne %l3" : "+S"(x), "+D"(y) : "r"(x) :: indirect, fallthrough);
fallthrough:
return y;
indirect:
return -2;
}
// test6: Expect no diagnostics.
int test6(unsigned int *x) {
unsigned int val;
// See through casts and unary operators.
asm goto("nop" : "=r" (*(unsigned int *)(&val)) ::: indirect);
*x = val;
return 0;
indirect:
return -1;
}
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