diff clang/test/Sema/warn-bitwise-compare.c @ 150:1d019706d866

LLVM10
author anatofuz
date Thu, 13 Feb 2020 15:10:13 +0900
parents
children c4bab56944e8
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/clang/test/Sema/warn-bitwise-compare.c	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,48 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-bitwise-compare %s
+// RUN: %clang_cc1 -fsyntax-only -verify -Wall -Wno-unused %s
+
+#define mydefine 2
+
+enum {
+  ZERO,
+  ONE,
+};
+
+void f(int x) {
+  if ((8 & x) == 3) {}  // expected-warning {{bitwise comparison always evaluates to false}}
+  if ((x & 8) == 4) {}  // expected-warning {{bitwise comparison always evaluates to false}}
+  if ((x & 8) != 4) {}  // expected-warning {{bitwise comparison always evaluates to true}}
+  if ((2 & x) != 4) {}  // expected-warning {{bitwise comparison always evaluates to true}}
+  if ((x | 4) == 3) {}  // expected-warning {{bitwise comparison always evaluates to false}}
+  if ((x | 3) != 4) {}  // expected-warning {{bitwise comparison always evaluates to true}}
+  if ((5 | x) != 3) {}  // expected-warning {{bitwise comparison always evaluates to true}}
+  if ((x & 0x15) == 0x13) {} // expected-warning {{bitwise comparison always evaluates to false}}
+  if ((0x23 | x) == 0x155){} // expected-warning {{bitwise comparison always evaluates to false}}
+
+  if (!!((8 & x) == 3)) {}  // expected-warning {{bitwise comparison always evaluates to false}}
+  int y = ((8 & x) == 3) ? 1 : 2;  // expected-warning {{bitwise comparison always evaluates to false}}
+
+  if ((x & 8) == 8) {}
+  if ((x & 8) != 8) {}
+  if ((x | 4) == 4) {}
+  if ((x | 4) != 4) {}
+
+  if ((x & 9) == 8) {}
+  if ((x & 9) != 8) {}
+  if ((x | 4) == 5) {}
+  if ((x | 4) != 5) {}
+
+  if ((x & mydefine) == 8) {}
+  if ((x | mydefine) == 4) {}
+}
+
+void g(int x) {
+  if (x | 5) {}  // expected-warning {{bitwise or with non-zero value always evaluates to true}}
+  if (5 | x) {}  // expected-warning {{bitwise or with non-zero value always evaluates to true}}
+  if (!((x | 5))) {}  // expected-warning {{bitwise or with non-zero value always evaluates to true}}
+
+  if (x | -1) {}  // expected-warning {{bitwise or with non-zero value always evaluates to true}}
+  if (x | ONE) {}  // expected-warning {{bitwise or with non-zero value always evaluates to true}}
+
+  if (x | ZERO) {}
+}