alexandru-dinu / igcc Goto Github PK

One of the ways to cut down on the overhead of repeated compilation is to make a precompiled header. The current set up is basically ready: boilerplate.h is always included, and with bits/stdc++.h it's got almost the entire standard library.

In fact, bits/stdc++.h states plainly at the top:

/** @file stdc++.h
 *  This is an implementation file for a precompiled header.
 */

That's how it's supposed to be used!

But how do we really do it?

• The config file needs a new pch_command option to run gcc -x c++-header $header -o $pcheader. This helps interaction with #10.
• Use -include (or -include-pch in clang) in the compiler invocation to get it to include. Doing it via command line lets us avoid writing to the igcc install directory, which can have permission issues. It does prevent users from opting out the boilerplate though.

I would be interested to know how I can switch on pure C support. I managed to adjust the compiler settings in the config/config.yaml and adjusted the "sourcecode" which was weirdly not in a .yaml file under config but in libigcc/source_code.py

But after that there was weirdly zero output by the repl. I tried generic statements like 1+4 or foo() and also printf(foo) but none of theme produced any output. I guess this might be because I disabled the cryptic boilerplate.h?

• arrows
• jump to start / end
• etc

https://docs.python.org/3/library/readline.html

When I try to run anything (after writing .h), I get the following error:

<stdin>:1:10: fatal error: boilerplate.h: No such file or directory
compilation terminated.

This happened when I ran #include <iostream> and printf( "h" );.

Steps to reproduce:

1. run .h
2. run #include <iostream>
3. see error and run .e
4. run printf( "any string" );
5. same as 3

Right now, errors can be tolerated until the code compiles.
However, this is both ugly and inefficient (as gcc is invoked after each line).

Proposal:

• add multi-line support, enabled by default
• maybe enclosed in .{, .} - similar to ghci

$ ./igcc -I libigcc
[1] .{
 >    int x = 0;
 >    for (int i = 1; i < 5; ++i) {
 >        x += i;
 >    }
 >  .}
[2] cout << x << endl;
10

Make explicit:

• C vs C++
• gcc vs g++

More clear compared to os.path.join.

Set up a simple workflow for running all tests under tests/.

The original tests are a bit messy and disorganized.
We should switch to pytest and make it part of the CI GitHub workflow.

• devise initial tests
• integrate with the GitHub workflow
• add coverage badge