Impact to Newly-compiled C binaries:

When code is recompiled, standard development practices should catch any problems that are caused by changes in the uid_t and gid_t type.

Problem areas to be aware of include the following:

1 #include <unistd.h>
2 #include <stdlib.h>
3 #include <stdio.h>
4
5 int
6 main(void)
7 {
8 uid_t negone = -1;
9
10 if (getuid() < 0)
11 exit(1);
12
13 (void) setreuid(negone, getuid());
14
15 (void) printf("%ld\n", getuid());
16
17 return (0);
18 }

• The following warning is generated by Sun's Studio 11 compiler:

  "uid.c", line 8: warning: initializer does not fit or is out of range: -1"

• The following warnings are generated by Studio 11 lint:

  ((8) warning: constant truncated by assignment

  (8) warning: initializer will be sign-extended: -1

  (10) warning: suspicious comparison of unsigned with 0: op "<"

  function argument ( number ) type inconsistent with format

• The following warnings are generated by gcc -Wall -Wextra:

  uid.c:10: warning: comparison of unsigned expression < 0 is always false

  uid.c:15: warning: long int format, uid_t arg (arg 2)

Newly-compiled C binaries can be intermingled with old objects and system objects. The size of the type has not changed.