this post was submitted on 31 Aug 2023
48 points (98.0% liked)
Programming
17511 readers
43 users here now
Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!
Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.
Hope you enjoy the instance!
Rules
Rules
- Follow the programming.dev instance rules
- Keep content related to programming in some way
- If you're posting long videos try to add in some form of tldr for those who don't want to watch videos
Wormhole
Follow the wormhole through a path of communities !webdev@programming.dev
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
The unnamed language that is compiled by
cc.To elaborate... C[++] is really two different languages, with mostly distinct feature sets, handled in most cases by different compilers, interpreters, parsers, etc.
The unnamed language with keywords like
#ifdefand#includewhich produces text output is a templating system that is functionally independent of the unnamed language with keywords likeforandunsignedwhich actually compiles to a binary.You can use
cppto run all the logic and conditionals in that first language to produce output, even if you replace the second language with something else like python or assembly.You can use
ccto compile that second language from source to binary, without support from the preprocessor.That second language, the one that
ccunderstands and compiles, does not have the ability to import functions or values or whatever from other files.I'd argue that's not true. That's what the extern keyword is for. If you do
#include, you don't get the actualprintffunction defined by the preprocessor. You just get an extern declaration (though extern is optional for function signatures). The preprocessed source code that is fed toccis still not complete, and cannot be used until it is linked to an object file that definesprintf. So really, the unnamed "C preprocessor output language" can access functions or values from elsewhere.No, it can't. The compiler can't do anything with content from any file not explicitly passed to it. You're mixing up the compiler and the linker (and the linker has nothing to do with either language, it can link binaries compiled from any language).
Holy shit this is fascinating!