• Justin Stitt's avatar
    ntb: idt: fix clang -Wformat warnings · a44252d5
    Justin Stitt authored
    When building with Clang we encounter these warnings:
    | drivers/ntb/hw/idt/ntb_hw_idt.c:2409:28: error: format specifies type
    | 'unsigned char' but the argument has type 'int' [-Werror,-Wformat]
    | "\t%hhu-%hhu.\t", idx + cnt - 1);
    -
    | drivers/ntb/hw/idt/ntb_hw_idt.c:2438:29: error: format specifies type
    | 'unsigned char' but the argument has type 'int' [-Werror,-Wformat]
    | "\t%hhu-%hhu.\t", idx + cnt - 1);
    -
    | drivers/ntb/hw/idt/ntb_hw_idt.c:2484:15: error: format specifies type
    | 'unsigned char' but the argument has type 'int' [-Werror,-Wformat], src);
    
    For the first two warnings the format specifier used is `%hhu` which
    describes a u8. Both `idx` and `cnt` are u8 as well. However, the
    expression as a whole is promoted to an int as you cannot get
    smaller-than-int from addition. Therefore, to fix the warning, use the
    promoted-to-type's format specifier -- in this case `%d`.
    
    example:
    ``
    uint8_t a = 4, b = 7;
    int size = sizeof(a + b - 1);
    printf("%d\n", size);
    // output: 4
    ```
    
    For the last warning, src is of type `int` while the format specifier
    describes a u8. The fix here is just to use the proper specifier `%d`.
    
    See more:
    (https://wiki.sei.cmu.edu/confluence/display/c/INT02-C.+Understand+integer+conversion+rules)
    "Integer types smaller than int are promoted when an operation is
    performed on them. If all values of the original type can be represented
    as an int, the value of the smaller type is converted to an int;
    otherwise, it is converted to an unsigned int."
    
    Link: https://github.com/ClangBuiltLinux/linux/issues/378Signed-off-by: default avatarJustin Stitt <justinstitt@google.com>
    Acked-by: default avatarSerge Semin <fancer.lancer@gmail.com>
    Signed-off-by: default avatarJon Mason <jdmason@kudzu.us>
    a44252d5
ntb_hw_idt.c 90.1 KB