https://gcc.gnu.org/g:8c635072ae68f60f14333cf113e75fa25a55becf
commit r14-11387-g8c635072ae68f60f14333cf113e75fa25a55becf
Author: Marek Polacek <pola...@redhat.com>
Date: Tue Mar 4 13:07:27 2025 -0500
c++: disable -Wnonnull in unevaluated context [PR115580]
This PR complains that we issue a -Wnonnull even in a decltype.
This fix disables even -Wformat and -Wrestrict. I think that's fine.
PR c++/115580
gcc/c-family/ChangeLog:
* c-common.cc (check_function_arguments): Return early if
c_inhibit_evaluation_warnings.
gcc/testsuite/ChangeLog:
* g++.dg/warn/Wnonnull16.C: New test.
Reviewed-by: Jason Merrill <ja...@redhat.com>
(cherry picked from commit 459c8a55567b06522e4b9cc0a4ef62f9d3024526)
Diff:
---
gcc/c-family/c-common.cc | 3 +++
gcc/testsuite/g++.dg/warn/Wnonnull16.C | 16 ++++++++++++++++
2 files changed, 19 insertions(+)
diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc
index d5b28efd6db4..0d05694b6d04 100644
--- a/gcc/c-family/c-common.cc
+++ b/gcc/c-family/c-common.cc
@@ -6160,6 +6160,9 @@ check_function_arguments (location_t loc, const_tree
fndecl, const_tree fntype,
{
bool warned_p = false;
+ if (c_inhibit_evaluation_warnings)
+ return warned_p;
+
/* Check for null being passed in a pointer argument that must be
non-null. In C++, this includes the this pointer. We also need
to do this if format checking is enabled. */
diff --git a/gcc/testsuite/g++.dg/warn/Wnonnull16.C
b/gcc/testsuite/g++.dg/warn/Wnonnull16.C
new file mode 100644
index 000000000000..8740f351ac76
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wnonnull16.C
@@ -0,0 +1,16 @@
+// PR c++/115580
+// { dg-do compile { target c++11 } }
+
+class WithMember {
+public:
+ int foo();
+};
+
+decltype(((WithMember*)nullptr)->foo()) footype; // { dg-bogus "pointer is
null" }
+
+int f(void*) __attribute__((nonnull));
+
+void g()
+{
+ [[maybe_unused]] decltype(f(nullptr)) b; // { dg-bogus "non-null" }
+}
