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c++gccclanggmp

Clang error on GMP memory management functions

I have some code that uses GMP which compiles and runs fine with g++.

...
// get ptrs to GMP memory management functions
void *(*alloc_func_ptr) (size_t);
void *(*free_func_ptr) (void *, size_t);
mp_get_memory_functions(&alloc_func_ptr, NULL, &free_func_ptr);
...

But when i compile it with the most recent clang++ it throws this error

gmpxx_boost_serialization.h:127: error: no matching function for call to '__gmp_get_memory_functions'
mp_get_memory_functions(&alloc_func_ptr, NULL, &free_func_ptr);

where mp_get_memory_functions is a macro 

#define mp_get_memory_functions __gmp_get_memory_functions
__GMP_DECLSPEC void mp_get_memory_functions (void *(**) (size_t),
                  void *(**) (void *, size_t, size_t),
                  void (**) (void *, size_t)) __GMP_NOTHROW;

Why does clang complain?

Solution

  • try changing:

    void *(*free_func_ptr) (void *, size_t);

    to:

    void (*free_func_ptr) (void *, size_t);

    As per the declaration, third argument to "mp_get_memory_functions" is address of the function pointer ( to function which returns "void" and not "void *" )