Question

The following code when compiled give this error I cannot understand why this is happening.
each line of the switch statement has this error. This code was taken from a code which was compiling perfectly with g++ but I don’t understand what is the problem with gcc.

void 
str_murmurhash3_x64_128 ( const void * key, const int len,
                           const uint32_t seed, void * out )
{
    const uint8_t * data = (const uint8_t*)key;
    const int nblocks = len / 16;

    uint64_t h1 = seed;
    uint64_t h2 = seed;

    uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);
    uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);

    //----------
    // body

    const uint64_t * blocks = (const uint64_t *)(data);
    int i;
    for(i = 0; i < nblocks; i++)
    {
        uint64_t k1 = getblock(blocks,i*2+0);
        uint64_t k2 = getblock(blocks,i*2+1);

        k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;

        h1 = ROTL64(h1,27); h1 += h2; h1 = h1*5+0x52dce729;

        k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;

        h2 = ROTL64(h2,31); h2 += h1; h2 = h2*5+0x38495ab5;
    }

    //----------
    // tail

    const uint8_t * tail = (const uint8_t*)(data + nblocks*16);

    uint64_t k1 = 0;
    uint64_t k2 = 0;

    switch(len & 15)
    {
        case 15: k2 ^= uint64_t(tail[14]) << 48;
        case 14: k2 ^= uint64_t(tail[13]) << 40;
        case 13: k2 ^= uint64_t(tail[12]) << 32;
        case 12: k2 ^= uint64_t(tail[11]) << 24;
        case 11: k2 ^= uint64_t(tail[10]) << 16;
        case 10: k2 ^= uint64_t(tail[ 9]) << 8;
        case  9: k2 ^= uint64_t(tail[ 8]) << 0;
                k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;

        case  8: k1 ^= uint64_t(tail[ 7]) << 56;
        case  7: k1 ^= uint64_t(tail[ 6]) << 48;
        case  6: k1 ^= uint64_t(tail[ 5]) << 40;
        case  5: k1 ^= uint64_t(tail[ 4]) << 32;
        case  4: k1 ^= uint64_t(tail[ 3]) << 24;
        case  3: k1 ^= uint64_t(tail[ 2]) << 16;
        case  2: k1 ^= uint64_t(tail[ 1]) << 8;
        case  1: k1 ^= uint64_t(tail[ 0]) << 0;
                k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
    };

    //----------
    // finalization

    h1 ^= len; h2 ^= len;

    h1 += h2;
    h2 += h1;

    h1 = fmix(h1);
    h2 = fmix(h2);

    h1 += h2;
    h2 += h1;

    ((uint64_t*)out)[0] = h1;
    ((uint64_t*)out)[1] = h2;
}

The following is th error and all line number specified in error corresponds to lines inside switch case.

murmurhash3.c:103:18: error: expected expression before ‘uint64_t’
murmurhash3.c:104:18: error: expected expression before ‘uint64_t’
murmurhash3.c:105:18: error: expected expression before ‘uint64_t’
murmurhash3.c:106:18: error: expected expression before ‘uint64_t’
murmurhash3.c:107:18: error: expected expression before ‘uint64_t’
murmurhash3.c:108:18: error: expected expression before ‘uint64_t’
murmurhash3.c:109:18: error: expected expression before ‘uint64_t’
murmurhash3.c:112:18: error: expected expression before ‘uint64_t’
murmurhash3.c:113:18: error: expected expression before ‘uint64_t’
murmurhash3.c:114:18: error: expected expression before ‘uint64_t’
murmurhash3.c:115:18: error: expected expression before ‘uint64_t’
murmurhash3.c:116:18: error: expected expression before ‘uint64_t’
murmurhash3.c:117:18: error: expected expression before ‘uint64_t’
murmurhash3.c:118:18: error: expected expression before ‘uint64_t’
murmurhash3.c:119:18: error: expected expression before ‘uint64_t’

Any help is appreciated.

Answer 1

You have a syntax error:

case 15: k2 ^= uint64_t(tail[14]) << 48;

Try instead this:

case 15: k2 ^= ((uint64_t)tail[14]) << 48;

Also, do you want the fall-through behavior? If not, do add break; after each case statement.