View Compilation Error

0_0_38463739_3956.cpp:2:30: error: 'malloc' was not declared in this scope
 char *p = (char *)malloc(size) + size;
                              ^
0_0_38463739_3956.cpp:3:28: error: expected ')' before '::' token
 __asm__("movq %0, %%rsp\n" :: "r"(p));
                            ^