From: Marek Polacek <polacek@redhat.com>
Date: Wed, 12 May 2021 15:19:13 +0000 (-0400)
Subject: c++: Disable -Wint-in-bool-context in instantiations
X-Git-Tag: basepoints/gcc-13~7560
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3a2b12bc5a7da7f0c5cf2ef4879d435a02feda8d;p=thirdparty%2Fgcc.git

c++: Disable -Wint-in-bool-context in instantiations

This warning is of questionable value when it's emitted when
instantiating a template, as in the following testcase.  It could be
silenced by writing hb(i) << 1 instead of 2 * hb(i) but that's
unnecessary obfuscation.

gcc/cp/ChangeLog:

	* pt.c (tsubst_copy_and_build): Add warn_int_in_bool_context
	sentinel.

gcc/testsuite/ChangeLog:

	* g++.dg/warn/Wint-in-bool-context-2.C: New test.
---

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 85c05af42ed4..d7d6a3f2c14a 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -19801,6 +19801,7 @@ tsubst_copy_and_build (tree t,
 
 	warning_sentinel s(warn_useless_cast);
 	warning_sentinel s2(warn_ignored_qualifiers);
+	warning_sentinel s3(warn_int_in_bool_context);
 	switch (TREE_CODE (t))
 	  {
 	  case CAST_EXPR:
diff --git a/gcc/testsuite/g++.dg/warn/Wint-in-bool-context-2.C b/gcc/testsuite/g++.dg/warn/Wint-in-bool-context-2.C
new file mode 100644
index 000000000000..6cb482d4dc9b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wint-in-bool-context-2.C
@@ -0,0 +1,16 @@
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wint-in-bool-context" }
+
+unsigned hb(unsigned i) { return ~i; }
+
+template<typename T>
+void f(int i)
+{
+  auto l = [i]() { return T(2 * hb(i)); }; // { dg-bogus "in boolean context" }
+  (void) l;
+}
+
+int main()
+{
+  f<bool>(0);
+}