procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

c++: format attribute redeclaration [PR116954]

Browse source 
Here when merging the two decls, remove_contract_attributes loses
ATTR_IS_DEPENDENT on the format attribute, so apply_late_template_attributes
just returns, so the attribute doesn't get propagated to the type where the
warning looks for it.

Fixed by using copy_node instead of tree_cons to preserve flags.

	PR c++/116954

gcc/cp/ChangeLog:

	* contracts.cc (remove_contract_attributes): Preserve flags
	on the attribute list.

gcc/testsuite/ChangeLog:

	* g++.dg/warn/Wformat-3.C: New test.
This commit is contained in:
Jason Merrill 2025-04-16 11:15:14 -04:00
parent 6b4569a3eb
commit b0d7d644f3
2 changed files with 24 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
gcc/cp/contracts.cc
View file

@ -863,7 +863,11 @@ remove_contract_attributes (tree fndecl)
tree list = NULL_TREE;
for (tree p = DECL_ATTRIBUTES (fndecl); p; p = TREE_CHAIN (p))
if (!cxx_contract_attribute_p (p))
list = tree_cons (TREE_PURPOSE (p), TREE_VALUE (p), list);
{
tree nl = copy_node (p);
TREE_CHAIN (nl) = list;
list = nl;
}
DECL_ATTRIBUTES (fndecl) = nreverse (list);
}

19
gcc/testsuite/g++.dg/warn/Wformat-3.C Normal file
View file

@ -0,0 +1,19 @@
// PR c++/116954
// { dg-additional-options -Wformat }
#ifndef WORKS
template<int N>
int fn(char (&buf)[N], const char fmt[], ...)
__attribute__ ((__format__ (__printf__, 2, 3)));
#endif
template<int N>
__attribute__ ((__format__ (__printf__, 2, 3)))
int fn(char (&)[N], const char [], ...)
{ return 0; }
int main()
{
char buf[20];
return fn(buf, "%s", 42); /* { dg-warning "Wformat" } */
}