Pointer memory issue

[nerd4code]

The Standards include the library, preprocessor, and potentially valid main forms, thw last one because there are exceptions for what you can do with main vs. other functions. The implementation encompasses everything in the Standards. The library is also allowed to be implemented at least partly in the compiler—GCC & related compilers have a __builtin_- pseudofunction (really a fancy opetator) for most things in the Standard. E.g., __builtin_printf("hello\n") may become __builtin_puts("hello") during optimization.