Comment author: administrator

"size_is" attribute is handled wrong for typedefs:

typedef struct {
int len;
[size_is(len)] int* data; /* OK */
} STRUCT1;

typedef int* PINT;
typedef struct {
int len;
[size_is(len)] PINT data;
/* Warning: attribute `size_is' unknown, malformed
or not applicable here, ignored. */
} STRUCT2;

For Camlidl, a "typedef" is not a macro -- it's a real declaration
that causes conversion functions for the defined type to be generated.
From this standpoint, it makes no sense to modify the type a posteriori
with a size_is attribute. In other terms, [size_is(...)] is
syntactically part of an array or pointer type
[size_is(...)] ty * foo
or
[size_is(...)] ty foo[]
but cannot be applied a posteriori to a named pointer or array type.

The MIDL spec isn't too clear about this, but all the examples it shows
are of the two forms above.

This is like the "string" attribute problem I reported before.

It's subtly different: your example was

    typedef char MYCHAR;
    [string] MYCHAR * x;

Here [string] is part of a pointer type expression, so it can be
parsed correctly as a string type.

• Xavier Leroy

Comment author: administrator

Normal behavior.

Comment author: administrator

Xavier Leroy Xavier.Leroy@inria.fr writes:

"size_is" attribute is handled wrong for typedefs:

typedef struct {
int len;
[size_is(len)] int* data; /* OK */
} STRUCT1;

typedef int* PINT;
typedef struct {
int len;
[size_is(len)] PINT data;
/* Warning: attribute `size_is' unknown, malformed
or not applicable here, ignored. */
} STRUCT2;

For Camlidl, a "typedef" is not a macro -- it's a real declaration
that causes conversion functions for the defined type to be generated.
From this standpoint, it makes no sense to modify the type a posteriori
with a size_is attribute. In other terms, [size_is(...)] is
syntactically part of an array or pointer type
[size_is(...)] ty * foo
or
[size_is(...)] ty foo[]
but cannot be applied a posteriori to a named pointer or array type.

The MIDL spec isn't too clear about this, but all the examples it shows
are of the two forms above.

Unfortunately, all examples are taken from the real Microsoft sources
(wtypes.idl):

typedef struct _SECURITY_ATTRIBUTES {
DWORD nLength;
[size_is(nLength)] LPVOID lpSecurityDescriptor;
BOOL bInheritHandle;
} SECURITY_ATTRIBUTES, *PSECURITY_ATTRIBUTES, *LPSECURITY_ATTRIBUTES;

OK, Microsoft docs has never been accurate, so you can mark it as "not a
bug" -- anyway I can edit that manually, inserting necessary #ifs.

Hope to hear from you soon,
Dmitry