https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87588
Bug ID: 87588
Summary: gcc does not warn about unused about unused variable
which references to itself
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: gcc at breakpoint dot cc
Target Milestone: ---
The .c file:
---->8-----
struct list {
struct list *prev, *next;
};
struct mutex {
struct list waiters;
};
static struct mutex mutex = \
{.waiters = {.prev = &mutex.waiters, .next = &mutex.waiters}};
static int a;
static int *b = &a;
---->8-----
produces:
gcc -o a.o a.c -c -O2 -Wall
a.c:14:13: warning: 'b' defined but not used [-Wunused-variable]
14 | static int *b = &a;
| ^
Would it be possible to also warn that the variable 'mutex' is unused? Except
that its member (.list.prev) is referenced to itself, it is not used outside of
that "initialization" construct.
