Conversation

Notices

1. Embed this notice
   mcc (mcc@mastodon.social)'s status on Tuesday, 06-Feb-2024 18:00:02 JST mcc

   @megmac C/C++ is a special hell because often you can import a symbol by *accident*. So code will work in one project and then you'll paste it into another and suddenly a critical symbol isn't found, because in the original project you included B.h which included A.h because nobody clearly told you in the first place you needed to include A.h.

   • clacke likes this.
   • Embed this notice
     mcc (mcc@mastodon.social)'s status on Tuesday, 06-Feb-2024 18:00:10 JST mcc

     in reply to

     • Fiona :heart_trans:
     • Garrett Wollman

     @wollman @airtower @megmac Maybe symbol import by textual inclusion is not actually a good approach

     clacke likes this.
   • Embed this notice
     Garrett Wollman (wollman@mastodon.social)'s status on Tuesday, 06-Feb-2024 18:00:11 JST Garrett Wollman

     in reply to

     • Fiona :heart_trans:

     @airtower @mcc @megmac There was kind of a religious war about this, with different people arguing that either all header files should be self-contained or that no header file should include any other (user-visible) header file, because namespace pollution. POSIX adopted the former, but also introduced a lot of new typedefs which meant that anyone doing anything nontrivial had to follow suit (because C doesn't have incomplete typedefs) even if most clients would never use them.

   • Embed this notice
     Fiona :heart_trans: (airtower@queer.af)'s status on Tuesday, 06-Feb-2024 18:00:12 JST Fiona :heart_trans:

     in reply to

     @mcc @megmac Or B.h uses a symbol declared in A.h but doesn't explicitly include it. If you include A.h then B.h it works, if you include B.h first you get implicit declarations and things break in weird ways.