• Gustavo A. R. Silva's avatar
    perf branch: Replace zero-length array with flexible-array · ffe7428e
    Gustavo A. R. Silva authored
    The current codebase makes use of the zero-length array language
    extension to the C90 standard, but the preferred mechanism to declare
    variable-length types such as these ones is a flexible array
    member[1][2], introduced in C99:
    
    struct foo {
            int stuff;
            struct boo array[];
    };
    
    By making use of the mechanism above, we will get a compiler warning in
    case the flexible array does not occur last in the structure, which will
    help us prevent some kind of undefined behavior bugs from being
    inadvertently introduced[3] to the codebase from now on.
    
    Also, notice that, dynamic memory allocations won't be affected by this
    change:
    
    "Flexible array members have incomplete type, and so the sizeof operator
    may not be applied. As a quirk of the original implementation of
    zero-length arrays, sizeof evaluates to zero."[1]
    
    sizeof(flexible-array-member) triggers a warning because flexible array
    members have incomplete type[1]. There are some instances ...
    ffe7428e
branch.h 2.01 KB