Wishlist : compiler improvements

[staalmannen]

Below a wishlist of stuff that would be nice to add to the compiler

• deal with 0x hexadecimal numbers with a decimal point!
• Be able to deal with 0x(hexadecimal)p(2^x) type numbers.
• Variable-length arrays (VLAs)
• a GAS format .s compiler
• C99 compatibility
• compiler support for <complex.h> type functions (like 1.0fi for defining _Complex_I and typeof for tgmath.h)
• C11 compatibility
• C23 compatibility

[staalmannen]

An overview of compiler improvements and TODOs in APExp
https://github.com/staalmannen/APExp/blob/main/apexp_compiler_improvements.md

This document outlines missing features for C99 compatibility

https://github.com/staalmannen/APExp/blob/main/sys/src/cmd/cc/c99

This document outlines changes needed for C11, C23 etc

https://github.com/staalmannen/APExp/blob/main/sys/src/cmd/cc/c11_c23

[staalmannen]

Something that could be cool for the future of APExp in the compiler space:

https://c9x.me/compile/

https://sr.ht/~mcf/cproc/

[staalmannen]

hex float seems to be solved - Several objects of the musl math library are now successfully compiling.

1477be0

The patch will probably not go upstream since it was vibe coded with claude.ai. It could however serve as inspiration if someone wants to write a proper patch that could be accepted upstream.

[staalmannen]

I experimented with letting claude.ai implement compiler VLA support too.
This patch is more invasive than the hex float, so take care if you play with it.

896c080

I will be testing it in APExp and keep it in if it works. One big issue for me is to find and undo all hacks I have done over the years to circumvent the lack of VLA support. I think the easiest way to undo those hacks might be to gradually just upgrade all ports when I know that the VLA patch is working.

[staalmannen]

Experimental small patch for C99 compound literal support
8f76177

[staalmannen]

Experimental claude.ai - generated patch for _Complex support
856e0c9

Just like the VLA. Be careful. Potentially invasive. I will keep it in APExp for experiments.

[staalmannen]

C99 basically considered complete. Some C11/C23 features have been added to the compiler.

https://github.com/staalmannen/APExp/blob/main/apexp_compiler_improvements.md

[staalmannen]

Note to self: The goken9cc project has merged improvements from Go and Inferno into kencc. There might be a lot of interesting things to "steal" from there.

https://github.com/aryx/goken9cc

• DWARF2 debugging symbols
• ???