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c - Explicit ignore warning from -Wcast-qual: cast discards ‘__attribute__((const))’ qualifier from pointer target type

static char buf[8];
void foo(){
    const char* ptr = buf;
    /* ... */
    char* q = (char*)ptr;
}

The above snippet will generate "warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual]". I like -Wcast-qual since it can help me from accidentally writing to memory I shouldn't write to.

But now I want to cast away const for only a single occurrence (not for the entire file or project). The memory it is pointing to is writable (just like buf above). I'd rather not drop const from ptr since it is used elsewhere and keeping to pointers (one const and one non-const) seems like a worse idea.

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#include <stdint.h>

const char * ptr = buf;
....
char * p = (char *)(uintptr_t)ptr;

Or, without stdint.h:

char *  p = (char *)(unsigned long)ptr;

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