Since r267272, which added location wrappers, cp_fold loses
TREE_NO_WARNING on a MODIFY_EXPR that finish_parenthesized_expr set, and
that results in a bogus -Wparentheses warning.
I.e., previously we had "b = 1" but now we have "VIEW_CONVERT_EXPR<bool>(b) = 1"
and cp_fold_maybe_rvalue folds away the location wrapper and so we do
2718 x = fold_build2_loc (loc, code, TREE_TYPE (x), op0, op1);
in cp_fold and the flag is lost.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/10/9?
PR c++/95344
* cp-gimplify.c (cp_fold) <case MODIFY_EXPR>: Set TREE_NO_WARNING.
* c-c++-common/Wparentheses-2.c: New test.
---
gcc/cp/cp-gimplify.c | 5 ++++-
gcc/testsuite/c-c++-common/Wparentheses-2.c | 18 ++++++++++++++++++
2 files changed, 22 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/c-c++-common/Wparentheses-2.c
diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c
index 53d715dcd89..8b505dd878c 100644
--- a/gcc/cp/cp-gimplify.c
+++ b/gcc/cp/cp-gimplify.c
@@ -2745,7 +2745,10 @@ cp_fold (tree x)
x = org_x;
}
if (code == MODIFY_EXPR && TREE_CODE (x) == MODIFY_EXPR)
- TREE_THIS_VOLATILE (x) = TREE_THIS_VOLATILE (org_x);
+ {
+ TREE_THIS_VOLATILE (x) = TREE_THIS_VOLATILE (org_x);
+ TREE_NO_WARNING (x) = TREE_NO_WARNING (org_x);
+ }
break;
diff --git a/gcc/testsuite/c-c++-common/Wparentheses-2.c
b/gcc/testsuite/c-c++-common/Wparentheses-2.c
new file mode 100644
index 00000000000..1aa5d314ae7
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wparentheses-2.c
@@ -0,0 +1,18 @@
+// PR c++/95344 - bogus -Wparentheses warning.
+// { dg-do compile }
+// { dg-options "-Wparentheses" }
+
+#ifndef __cplusplus
+# define bool _Bool
+# define true 1
+# define false 0
+#endif
+
+void
+f (int i)
+{
+ bool b = false;
+ if (i == 99 ? (b = true) : false) // { dg-bogus "suggest parentheses" }
+ {
+ }
+}
base-commit: 56f03cd12be26828788a27f6f3c250041a958e45
--
Marek Polacek • Red Hat, Inc. • 300 A St, Boston, MA
