1 files changed, 82 insertions, 0 deletions
diff --git a/clang/test/Sema/constant-conversion.c b/clang/test/Sema/constant-conversion.c
new file mode 100644
index 0000000..1376333
--- /dev/null
+++ b/clang/test/Sema/constant-conversion.c
@@ -0,0 +1,82 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -triple x86_64-apple-darwin %s
+
+// This file tests -Wconstant-conversion, a subcategory of -Wconversion
+// which is on by default.
+
+// rdar://problem/6792488
+void test_6792488(void) {
+  int x = 0x3ff0000000000000U; // expected-warning {{implicit conversion from 'unsigned long' to 'int' changes value from 4607182418800017408 to 0}}
+}
+
+void test_7809123(void) {
+  struct { int i5 : 5; } a;
+
+  a.i5 = 36; // expected-warning {{implicit truncation from 'int' to bitfield changes value from 36 to 4}}
+}
+
+void test() {
+  struct { int bit : 1; } a;
+  a.bit = 1; // shouldn't warn
+}
+
+enum Test2 { K_zero, K_one };
+enum Test2 test2(enum Test2 *t) {
+  *t = 20;
+  return 10; // shouldn't warn
+}
+
+void test3() {
+  struct A {
+    unsigned int foo : 2;
+    int bar : 2;
+  };
+
+  struct A a = { 0, 10 };            // expected-warning {{implicit truncation from 'int' to bitfield changes value from 10 to -2}}
+  struct A b[] = { 0, 10, 0, 0 };    // expected-warning {{implicit truncation from 'int' to bitfield changes value from 10 to -2}}
+  struct A c[] = {{10, 0}};          // expected-warning {{implicit truncation from 'int' to bitfield changes value from 10 to 2}}
+  struct A d = (struct A) { 10, 0 }; // expected-warning {{implicit truncation from 'int' to bitfield changes value from 10 to 2}}
+  struct A e = { .foo = 10 };        // expected-warning {{implicit truncation from 'int' to bitfield changes value from 10 to 2}}
+}
+
+void test4() {
+  struct A {
+    char c : 2;
+  } a;
+
+  a.c = 0x101; // expected-warning {{implicit truncation from 'int' to bitfield changes value from 257 to 1}}
+}
+
+void test5() {
+  struct A {
+    _Bool b : 1;
+  } a;
+
+  // Don't warn about this implicit conversion to bool, or at least
+  // don't warn about it just because it's a bitfield.
+  a.b = 100;
+}
+
+void test6() {
+  // Test that unreachable code doesn't trigger the truncation warning.
+  unsigned char x = 0 ? 65535 : 1; // no-warning
+  unsigned char y = 1 ? 65535 : 1; // expected-warning {{changes value}}
+}
+
+void test7() {
+	struct {
+		unsigned int twoBits1:2;
+		unsigned int twoBits2:2;
+		unsigned int reserved:28;
+	} f;
+
+	f.twoBits1 = ~1; // expected-warning {{implicit truncation from 'int' to bitfield changes value from -2 to 2}}
+	f.twoBits2 = ~2; // expected-warning {{implicit truncation from 'int' to bitfield changes value from -3 to 1}}
+	f.twoBits1 &= ~1; // no-warning
+	f.twoBits2 &= ~2; // no-warning
+}
+
+void test8() {
+  enum E { A, B, C };
+  struct { enum E x : 1; } f;
+  f.x = C; // expected-warning {{implicit truncation from 'int' to bitfield changes value from 2 to 0}}
+}