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clinuxgccgmp

`#include <gmpxx.h>` fails to compile with `fatal error: iosfwd: No such file or directory`

I am trying to use the GMP library in my C program as follows:

/* gmp test */
#include <gmpxx.h>

main() {
  printf("yay, it works!\n");
}

and I am compiling this on Linux with gcc -o a.out my-c-program.c, but I get this error when compiling the #include <gmpxx.h> line above:

gcc -o a.out my-c-program.c
In file included from my-c-program.c:2:0:
/usr/include/gmpxx.h:34:18: fatal error: iosfwd: No such file or directory
compilation terminated.

Compilation exited abnormally with code 1 at Thu May  5 11:34:16

I looked at the gmpxx.h file under /usr/include/gmpxx.h, and on line 34, there is the line #include <iosfwd>, which explains the error. But how do I fix it? Am I missing a library? Or am I missing something in my gcc command?

Solution

  • The correct header name for GMP as C library is gmp.h.

    The gmpxx.h is suited for GMP's C++ Class Interface, which is built on top of gmp.h and requires to compile with C++ compiler such as g++.