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authorMarek Polacek <polacek@redhat.com>2015-04-30 13:20:03 +0000
committerMarek Polacek <mpolacek@gcc.gnu.org>2015-04-30 13:20:03 +0000
commit577cd070845fb8facf0a451aafe1e444b9374b08 (patch)
tree542480c9b7ef2c43959ef8a34b1d4b686702590a
parentbb83a43d6b768886ea4733ca6218f30d90ea0e15 (diff)
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c-common.c (maybe_warn_bool_compare): When comparing with 0/1, require that the non-constant be of a boolean type.
* c-common.c (maybe_warn_bool_compare): When comparing with 0/1, require that the non-constant be of a boolean type. * c-c++-common/Wbool-compare-3.c: New test. From-SVN: r222622
-rw-r--r--gcc/c-family/ChangeLog5
-rw-r--r--gcc/c-family/c-common.c11
-rw-r--r--gcc/testsuite/ChangeLog4
-rw-r--r--gcc/testsuite/c-c++-common/Wbool-compare-3.c30
4 files changed, 50 insertions, 0 deletions
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index c17ea5f..8c2e933 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,8 @@
+2015-04-30 Marek Polacek <polacek@redhat.com>
+
+ * c-common.c (maybe_warn_bool_compare): When comparing with 0/1,
+ require that the non-constant be of a boolean type.
+
2015-04-29 Josh Triplett <josh@joshtriplett.org>
* c-common.c (handle_section_attribute): Refactor to reduce
diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index 7d314f8..ada8e8a 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -11924,6 +11924,17 @@ maybe_warn_bool_compare (location_t loc, enum tree_code code, tree op0,
}
else if (integer_zerop (cst) || integer_onep (cst))
{
+ /* If the non-constant operand isn't of a boolean type, we
+ don't want to warn here. */
+ tree noncst = TREE_CODE (op0) == INTEGER_CST ? op1 : op0;
+ /* Handle booleans promoted to integers. */
+ if (CONVERT_EXPR_P (noncst)
+ && TREE_TYPE (noncst) == integer_type_node
+ && TREE_CODE (TREE_TYPE (TREE_OPERAND (noncst, 0))) == BOOLEAN_TYPE)
+ /* Warn. */;
+ else if (TREE_CODE (TREE_TYPE (noncst)) != BOOLEAN_TYPE
+ && !truth_value_p (TREE_CODE (noncst)))
+ return;
/* Do some magic to get the right diagnostics. */
bool flag = TREE_CODE (op0) == INTEGER_CST;
flag = integer_zerop (cst) ? flag : !flag;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e0df670..4557768 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2015-04-30 Marek Polacek <polacek@redhat.com>
+
+ * c-c++-common/Wbool-compare-3.c: New test.
+
2015-04-30 Paolo Carlini <paolo.carlini@oracle.com>
PR c++/57610
diff --git a/gcc/testsuite/c-c++-common/Wbool-compare-3.c b/gcc/testsuite/c-c++-common/Wbool-compare-3.c
new file mode 100644
index 0000000..bac4f47
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wbool-compare-3.c
@@ -0,0 +1,30 @@
+/* { dg-do compile } */
+/* { dg-options "-Wbool-compare" } */
+
+#ifndef __cplusplus
+# define bool _Bool
+#endif
+
+#define A 0
+#define B 1
+
+int
+foo (int i, bool b)
+{
+ int r = 0;
+
+ r += i <= (A || B);
+ r += i <= b;
+ r += i <= A;
+ r += i < (A || B);
+ r += i < b;
+ r += i < A;
+ r += i > (A || B);
+ r += i > b;
+ r += i > A;
+ r += i >= (A || B);
+ r += i >= b;
+ r += i >= A;
+
+ return r;
+}