From 5f8c3c8edff426fd87098f057688463107fcd9ce Mon Sep 17 00:00:00 2001 From: Michael Abbott Date: Tue, 12 Aug 2008 15:09:11 -0700 Subject: [PATCH] Make ioctl.h compatible with userland The attached patch seems to already exist in a number of branches -- it keeps popping up on Google for me, and is certainly already in Debian -- but is strangely absent from mainstream. The problem appears to be that the patched file ends up as part of the target toolchain, but unfortunately the gcc constant folding doesn't appear to eliminate the __invalid_size_argument_for_IOC value early enough. Certainly compiling C++ programs which use _IO... macros as constants fails without this patch. Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/ioctl.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/asm-generic/ioctl.h b/include/asm-generic/ioctl.h index 86418138557..15828b2d663 100644 --- a/include/asm-generic/ioctl.h +++ b/include/asm-generic/ioctl.h @@ -68,12 +68,16 @@ ((nr) << _IOC_NRSHIFT) | \ ((size) << _IOC_SIZESHIFT)) +#ifdef __KERNEL__ /* provoke compile error for invalid uses of size argument */ extern unsigned int __invalid_size_argument_for_IOC; #define _IOC_TYPECHECK(t) \ ((sizeof(t) == sizeof(t[1]) && \ sizeof(t) < (1 << _IOC_SIZEBITS)) ? \ sizeof(t) : __invalid_size_argument_for_IOC) +#else +#define _IOC_TYPECHECK(t) (sizeof(t)) +#endif /* used to create numbers */ #define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0) -- 2.41.0