Bizaare non-constant class sizes.

Andrew Over
Thu May 11 22:41:00 GMT 2000

On Fri, May 12, 2000 at 07:08:22AM +0200, Martin v. Loewis wrote:

> GCC 2.95 would (incorrectly) allow that fields of a class are
> variable-length arrays. That might cause the problem you see.

I'm not even using fixed-length arrays inside the class, so that's not
the cause.

> Please note that egcs-bugs is an address to report bugs, not one to
> ask questions about the compiler.

Maybe I didn't properly explain what's going on.

Consider the following (in a header file):

class a {
      int a;

class b {
      int b;

class c : public a, public b {
      int c;

Now, if I print sizeof(class c) in one file, I get 12.  If I do it in
a different file, I get 8 (clearly too small). foo = new c() in this
file results in a segfault.  Obviously the value should be constant
across every file that includes this definition.

I had a look through gnats for something similar, but without luck,
and was wondering if this bug had been reported before (or if there
was a workaround).

I'll try to obtain the .ii stuff tomorrow if I can't figure out a way
around this.


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