Broken RISC-V code in newlib

[Kito Cheng]

Hi Eric:

> diff --git a/newlib/libc/machine/riscv/sys/asm.h b/newlib/libc/machine/riscv/sys/asm.h
> index 0a354b220517..a9792e964ebc 100644
> --- a/newlib/libc/machine/riscv/sys/asm.h
> +++ b/newlib/libc/machine/riscv/sys/asm.h
> @@ -12,7 +12,9 @@
>  #ifndef _SYS_ASM_H
>  #define _SYS_ASM_H
>
> +#if !__ASSEMBLER__
>  #include <stdint.h>
> +#endif
>
>  /*
>   * Macros to handle different pointer/register sizes for 32/64-bit code
> @@ -22,13 +24,17 @@
>  # define SZREG 8
>  # define REG_S sd
>  # define REG_L ld
> +#if !__ASSEMBLER__
>  typedef uint64_t uintxlen_t;
> +#endif
>  #elif __riscv_xlen == 32
>  # define PTRLOG 2
>  # define SZREG 4
>  # define REG_S sw
>  # define REG_L lw
> +#if !__ASSEMBLER__
>  typedef uint32_t uintxlen_t;
> +#endif
>  #else
>  # error __riscv_xlen must equal 32 or 64
>  #endif

Seems like sys/asm.h is not the right place to put those C typedef and
also including #include <stdint.h>

Could you just create a xlenint.h in newlib/libc/machine/riscv/ then
include that by #include "xlenint.h" in those places you want to use?

Since uintxlen_t is not defined in either standard C or RISC-V
conventions, so I would like to prevent exposing that to users if
possible :)