https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99272
Bug ID: 99272
Summary: False positive -Wredundant-tags warning when reusing a
name
Product: gcc
Version: 10.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: headch at gmail dot com
Target Milestone: ---
$ cat test.cpp
struct foo {
int x;
};
struct bar {
struct foo foo;
};
$ g++-10.2.0 -Wall -Wextra -Wredundant-tags -std=c++2a -c test.cpp
test.cpp:6:2: warning: redundant class-key ‘struct’ in reference to ‘struct
foo’ [-Wredundant-tags]
6 | struct foo foo;
| ^~~~~~
| ------
But this is not redundant. Removing the word “struct” results in a compile
error:
$ g++-10.2.0 -Wall -Wextra -Wredundant-tags -std=c++2a -c test.cpp
test.cpp:6:6: error: declaration of ‘foo bar::foo’ changes meaning of ‘foo’
[-fpermissive]
6 | foo foo;
| ^~~
test.cpp:1:8: note: ‘foo’ declared here as ‘struct foo’
1 | struct foo {
| ^~~
Therefore I think -Wredundant-tags should not generate a warning in this
situation (the tag is not redundant).
