• Ard Biesheuvel's avatar
    ARM: 7822/1: add workaround for ambiguous C99 stdint.h types · 09096f6a
    Ard Biesheuvel authored
    The C99 types uintXX_t that are usually defined in 'stdint.h' are not as
    unambiguous on ARM as you would expect. For the types below, there is a
    difference on ARM between GCC built for bare metal ARM, GCC built for glibc
    and the kernel itself, which results in build errors if you try to build with
    -ffreestanding and include 'stdint.h' (such as when you include 'arm_neon.h'
    in order to use NEON intrinsics)
    
    As the typedefs for these types in 'stdint.h' are based on builtin defines
    supplied by GCC, we can tweak these to align with the kernel's idea of those
    types, so 'linux/types.h' and 'stdint.h' can be safely included from the same
    source file (provided that -ffreestanding is used).
    
                       int32_t         uint32_t               uintptr_t
    bare metal GCC     long            unsigned long          unsigned int
    glibc GCC          int             unsigned int           unsigned int
    kernel             int             unsigned int           unsigned long
    
    Acked by: Dave Martin <dave.martin@arm.com>
    Acked-by: default avatarNicolas Pitre <nico@linaro.org>
    Acked-by: default avatarMikael Pettersson <mikpe@it.uu.se>
    Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    09096f6a
types.h 1.37 KB