[Rd] gcc optimization flag when building R

Peter Dalgaard p.dalgaard at biostat.ku.dk
Fri Aug 20 20:15:13 CEST 2004

"Vadim Ogranovich" <vograno at evafunds.com> writes:

> Hi,
> I am building R on RH Linux 7.3 and I noticed that ./configure does not
> set the optimization flag, -O or -O2, for gcc, but does set for g++ and
> g77. Why is that? Should I try to set it manually, if yes how?
> Thanks,
> Vadim
> P.S. This is the bottom portion of the ./configure run
> R is now configured for i686-pc-linux-gnu
>   Source directory:          .
>   Installation directory:    /usr/local
>   C compiler:                gcc -D__NO_MATH_INLINES -mieee-fp -DNO_PURE
> -Wchar-subscripts -Wformat -Wimplicit -Wreturn-type -Wswitch -Wreorder
> -Wwrite-strings -Woverloaded-virtual -Wshadow -Wno-ctor-dtor-privacy
>   C++ compiler:              g++ -mieee-fp -g -O2
>   Fortran compiler:          g77 -mieee-fp -g -O2

Something appears to be setting a load of CFLAGS that are not usually
there, though. If you have set CFLAGS on the make line or in a config.site
file, just include -g -O2 

   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)             FAX: (+45) 35327907

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