Hello,
$ cat try.c
int main(void) {
struct X {
int s[20] : 1;
int *p : 2;
int (*f)(float) : 3;
} x;
return 0;
}
$ gcc -W -Wall -Wundef -Wendif-labels -Wshadow -Wpointer-arith -Wcast-align
-Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Winline
-Wdisabled-optimization -std=c99 -pedantic -O2 try.c
try.c: In function `main':
try.c:6: warning: unused variable `x'
$
I would have expected an error (or at least a warning) for the non-int
bitfields. C99, 6.7.2.1/4 says:
A bit-field shall have a type that is a qualified or unqualified version of
_Bool, signed int, unsigned int, or some other implementation-defined type.
int [20], int * and int (*)(float) aren't ints. I couldn't find anything about
bit-field extensions in `info gcc', so it doesn't seem to be
implementation-defined.
Is this a bug in gcc or am I missing something?
Lukas
--
Summary: gcc allows non-integral bitfield types
Product: gcc
Version: 3.4.3
Status: UNCONFIRMED
Severity: minor
Priority: P2
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: rwxr-xr-x at gmx dot de
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: i686-pc-linux-gnu
GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18498
