1 files changed, 123 insertions, 0 deletions
diff --git a/clang/test/Sema/unused-expr.c b/clang/test/Sema/unused-expr.c
new file mode 100644
index 0000000..9761116
--- /dev/null
+++ b/clang/test/Sema/unused-expr.c
@@ -0,0 +1,123 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s -Wno-unreachable-code
+
+int foo(int X, int Y);
+
+double sqrt(double X);  // implicitly const because of no -fmath-errno!
+
+void bar(volatile int *VP, int *P, int A,
+         _Complex double C, volatile _Complex double VC) {
+  
+  VP < P;              // expected-warning {{expression result unused}}
+  (void)A;
+  (void)foo(1,2);      // no warning.
+  
+  A < foo(1, 2);       // expected-warning {{expression result unused}}
+
+  foo(1,2)+foo(4,3);   // expected-warning {{expression result unused}}
+
+
+  *P;                  // expected-warning {{expression result unused}}
+  *VP;                 // no warning.
+  P[4];                // expected-warning {{expression result unused}}
+  VP[4];               // no warning.
+
+  __real__ C;          // expected-warning {{expression result unused}}
+  __real__ VC;
+  
+  // We know this can't change errno because of no -fmath-errno.
+  sqrt(A);  // expected-warning {{ignoring return value of function declared with const attribute}}
+}
+
+extern void t1();
+extern void t2();
+void t3(int c) {
+  c ? t1() : t2();
+}
+
+// This shouldn't warn: the expr at the end of the stmtexpr really is used.
+int stmt_expr(int x, int y) {
+  return ({int _a = x, _b = y; _a > _b ? _a : _b; });
+}
+
+void nowarn(unsigned char* a, unsigned char* b)
+{
+  unsigned char c = 1;
+  *a |= c, *b += c;
+
+
+  // PR4633
+  int y, x;
+  ((void)0), y = x;
+}
+
+void t4(int a) {
+  int b = 0;
+
+  if (a)
+    b < 1; // expected-warning{{expression result unused}}
+  else
+    b < 2; // expected-warning{{expression result unused}}
+    
+  while (1)
+    b < 3; // expected-warning{{expression result unused}}
+
+  do
+    b < 4; // expected-warning{{expression result unused}}
+  while (1);
+  
+  for (;;)
+    b < 5; // expected-warning{{expression result unused}}
+    
+  for (b < 1;;) {} // expected-warning{{expression result unused}}
+  for (;b < 1;) {}
+  for (;;b < 1) {} // expected-warning{{expression result unused}}
+}
+
+// rdar://7186119
+int t5f(void) __attribute__((warn_unused_result));
+void t5() {
+  t5f();   // expected-warning {{ignoring return value of function declared with warn_unused_result}}
+}
+
+
+int fn1() __attribute__ ((warn_unused_result));
+int fn2() __attribute__ ((pure));
+int fn3() __attribute__ ((const));
+// rdar://6587766
+int t6() {
+  if (fn1() < 0 || fn2(2,1) < 0 || fn3(2) < 0)  // no warnings
+    return -1;
+
+  fn1();  // expected-warning {{ignoring return value of function declared with warn_unused_result attribute}}
+  fn2(92, 21);  // expected-warning {{ignoring return value of function declared with pure attribute}}
+  fn3(42);  // expected-warning {{ignoring return value of function declared with const attribute}}
+  __builtin_fabsf(0); // expected-warning {{ignoring return value of function declared with const attribute}}
+  return 0;
+}
+
+int t7 __attribute__ ((warn_unused_result)); // expected-warning {{'warn_unused_result' attribute only applies to functions}}
+
+// PR4010
+int (*fn4)(void) __attribute__ ((warn_unused_result));
+void t8() {
+  fn4(); // expected-warning {{ignoring return value of function declared with warn_unused_result attribute}}
+}
+
+void t9() __attribute__((warn_unused_result)); // expected-warning {{attribute 'warn_unused_result' cannot be applied to functions without return value}}
+
+// rdar://7410924
+void *some_function(void);
+void t10() {
+  (void*) some_function(); //expected-warning {{expression result unused; should this cast be to 'void'?}}
+}
+
+void f(int i, ...) {
+    __builtin_va_list ap;
+    
+    __builtin_va_start(ap, i);
+    __builtin_va_arg(ap, int);
+    __builtin_va_end(ap);
+}
+
+// PR8371
+int fn5() __attribute__ ((__const));