Diagnostics · Unsafe Pointers

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diagnostics/unsafe_pointers.fl

// Intentionally rejected. Each function illustrates a separate restriction.
// Check: build/flecha --emit-llvm examples/diagnostics/unsafe_pointers.fl

unsafe void write(*i32 pointer) {
    *pointer = 42;
}

void missing_permission(*i32 pointer) {
    write(pointer);       // FLECHA-S0025: unsafe call.
    *pointer;             // FLECHA-S0025: unsafe read.
    *pointer = 42;        // FLECHA-S0025: unsafe write.
    &raw pointer;         // FLECHA-S0025: unsafe address creation.
}

unsafe void const_rules(*const i32 readOnly) {
    *readOnly = 42;        // FLECHA-S0005: read-only target.
    constptr i32 fixed = none;
    fixed = null;         // FLECHA-S0005: fixed pointer binding.
}

unsafe void uninitialized_pointer() {
    *i32 pointer;
    *pointer = 42;        // FLECHA-S0021: reads an uninitialized pointer.
}

unsafe void opaque_pointer(*void pointer) {
    *pointer;             // FLECHA-S0026: void has no readable value.
}