[LLVMdev] Does DragonEgg support parameters like -fno-builtin in clang?

Duncan Sands baldrick at free.fr
Wed Apr 10 01:31:12 PDT 2013

Hi Jeff,

> I have been using clang for quite a while, and I can use `clang -fno-builtin
> hello.c` to prevent the generation of llvm built-in functions, such as
> llvm.memset. Recently, I switched to gcc with DragonEgg, since the program to be
> built is originally designed to be compiled with gcc. I searched on the web, but
> did not find any information about how to set DragonEgg parameters. Could anyone
> please give me some help? Thanks in advance!

dragonegg just uses the same parameters as gcc.  However -fno-builtin has no
effect (this is a bug) because it is surprisingly tricky to get the appropriate
information from inside gcc.  To be more precise: it's not too hard to set up
something that works OK for C, but then it works poorly for Fortran and Ada.  I
didn't yet come up with a scheme that works well for all languages.

Ciao, Duncan.

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