Completion of error handling

[elfring]

Would you like to add more error handling for return values from functions like the following?

• fwrite ⇒ write_to_output
• malloc ⇒ main

[ianh]

The return value of malloc is already checked anywhere the src/alloc.h header is included (see src/alloc.h:37). I might as well add a similar check to the call to fwrite.

[ianh]

Added in ce800c8.

[ianh]

There are other calls to fwrite, but they should just be going to stdout/stderr. I'm not sure detecting errors there is worthwhile.

[elfring]

The return value of malloc is already checked

Would it be clearer to use your own function names directly instead of the applied renaming?

---

I suggest to avoid ignorance of return values a bit more. Would you like to detect every error situation as early as possible?

[ianh]

It may be slightly clearer, but I think it also makes the code harder to read. I only added those checks because of the WebAssembly target, where malloc failure actually happens somewhat frequently—on other platforms it's less of a concern.

[elfring]

A few update candidates were left over.