[PATCH] newlib-stdint.h: Remove 32 bit longs

Andy Ross andrew.j.ross@intel.com
Fri Aug 19 19:16:00 GMT 2016

We ran into this issue in the Zephyr project with our toolchain (gcc
built with --enable-newlib).  Basically GCC appears to be honoring a
legacy requirement to give newlib a "long" instead of "int" for
__INT32_TYPE__, which then leaks out through the current newlib
headers as a long-valued int32_t, which produces gcc warnings when a
uint32_t is passed to an unqualified printf format specifier like

But the newlib headers, if __INT32_TYPE__ is *not* defined by the
compiler, have code to chose a "int" over "long" immediately
thereafter.  It seems whatever requirement this was honoring isn't
valid anymore.

>From 784fb1760a930d0309f878bbae7bfd38137f5689 Mon Sep 17 00:00:00 2001
From: Andy Ross <andrew.j.ross@intel.com>
Date: Fri, 19 Aug 2016 09:40:42 -0700
Subject: [PATCH] newlib-stdint.h: Remove 32 bit longs

This would make __INT32_TYPE__ a "long" instead of an "int", which
would then percolate down in newlib's own headers into a typedef for
int32_t.  Which is wrong.  Newlib's headers, if __INT32_TYPE__ were
not defined, actually would chose an int for this type.  The comment
that newlib uses a 32 bit long appears to be a lie, perhaps

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
 gcc/config/newlib-stdint.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/gcc/config/newlib-stdint.h b/gcc/config/newlib-stdint.h
index eb99556..0275948 100644
--- a/gcc/config/newlib-stdint.h
+++ b/gcc/config/newlib-stdint.h
@@ -22,10 +22,9 @@ a copy of the GCC Runtime Library Exception along with this program;
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */

-/* newlib uses 32-bit long in certain cases for all non-SPU
-   targets.  */
+/* newlib used to use a 32-bit long, no longer */
 #ifndef STDINT_LONG32
-#define STDINT_LONG32 (LONG_TYPE_SIZE == 32)
+#define STDINT_LONG32 0

 #define SIG_ATOMIC_TYPE "int"

More information about the Newlib mailing list