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inttypes.h bug leads to inconsistent warnings cross platform


This code will compile warning free on some targets but not
on others. This issue should exist on all targets base on the
CPU architecture as shown below.

#include <stdio.h>
#include <inttypes.h>

void f( uintptr_t p )
  printf( "Value = %" PRIuPTR "\n", p );

This is a list of warning/no warning for every RTEMS target
that compiles on the head.

=== arm-rtems4.11-gcc - no warning
=== bfin-rtems4.11-gcc - warning
=== i386-rtems4.11-gcc - warning
=== lm32-rtems4.11-gcc - no warning
=== m68k-rtems4.11-gcc - warning
=== nios2-rtems4.11-gcc - no warning
=== or1k-rtems4.11-gcc - warning
=== powerpc-rtems4.11-gcc - no warning
=== sh-rtems4.11-gcc - no warning
=== sparc64-rtems4.11-gcc - no warning
=== sparc-rtems4.11-gcc - no warning
=== v850-rtems4.11-gcc - no warning

I have tracked this down to newlib's inttypes.h does not detect
when gcc defines integer pointer types to long. PRIuPTR turns
into "u" not "ul".

$ or1k-rtems4.11-gcc -dM -E - </dev/null | grep INTPTR_T
#define __INTPTR_TYPE__ long int
#define __UINTPTR_TYPE__ long unsigned int
$ arm-rtems4.11-gcc -dM -E - </dev/null | grep INTPTR_T
#define __INTPTR_TYPE__ int
#define __UINTPTR_TYPE__ unsigned int

On the above two targets __PTRDIFF_TYPE__ is the same.

The code in inttypes.h in question is:

# define __PRIPTR(x) __STRINGIFY(x)
# define __SCNPTR(x) __STRINGIFY(x)
#elif PTRDIFF_MAX <= __INTTYPES_EXP(LONG_MAX) || !defined(__have_longlong64)
# define __PRIPTR(x) __STRINGIFY(l##x)
# define __SCNPTR(x) __STRINGIFY(l##x)
# define __PRIPTR(x) __STRINGIFY(ll##x)
# define __SCNPTR(x) __STRINGIFY(ll##x)

Any thoughts on how to detect when it should use
"ul" for long uinptr_t instead of "u" for targets with
int uintptr_t?

I don't see any related variables that differ in the predefined
CPP macros except the actual type.


Joel Sherrill, Ph.D.             Director of Research & Development        On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
Support Available                (256) 722-9985

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