# \[PATCH 05/18\] arm64:uapi: set \_\_BITS\_PER\_LONG correctly for ILP32 and LP64

- From: Yury Norov \<hidden\>
- Date: 2016-08-17 11:47:52 
- List: linux-arm-kernel
- Page: https://ratatoskr.run/linux-arm-kernel/2016/08/4816389
- Thread: https://ratatoskr.run/linux-arm-kernel/2016/08/4816396/t.md

```text
From: Andrew Pinski <redacted>

Define __BITS_PER_LONG depending on the ABI used (i.e. check whether
__ILP32__ or __LP64__ is defined).  This is necessary for glibc to
determine the appropriate type definitions for the system call interface.

Signed-off-by: Andrew Pinski <redacted>
Signed-off-by: Philipp Tomsich <redacted>
Signed-off-by: Christoph Muellner <redacted>
Signed-off-by: Yury Norov <redacted>
Reviewed-by: David Daney <redacted>
---
 arch/arm64/include/uapi/asm/bitsperlong.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/uapi/asm/bitsperlong.h b/arch/arm64/include/uapi/asm/bitsperlong.h
index fce9c29..4265243 100644
--- a/arch/arm64/include/uapi/asm/bitsperlong.h
+++ b/arch/arm64/include/uapi/asm/bitsperlong.h
@@ -16,7 +16,14 @@
 #ifndef __ASM_BITSPERLONG_H
 #define __ASM_BITSPERLONG_H
 
-#define __BITS_PER_LONG 64
+#if defined(__LP64__)
+/* Assuming __LP64__ will be defined for native ELF64's and not for ILP32. */
+#  define __BITS_PER_LONG 64
+#elif defined(__ILP32__)
+#  define __BITS_PER_LONG 32
+#else
+#  error "Neither LP64 nor ILP32: unsupported ABI in asm/bitsperlong.h"
+#endif
 
 #include <asm-generic/bitsperlong.h>
 
-- 
2.7.4
```