Richard Fish wrote: > Gcc is (almost) always built with -O2 on Gentoo, but it does not > matter anyway. The CFLAGS that gcc is built with does not effect the > binaries it generates...only the code and the flags passed to gcc > during the compilation effect this. If your model were correct, you > would need a gcc built with -Os for using -Os, a gcc built with "-Os > -fweb" for building with "-Os -fweb", "-O3" for building with -O3, > "-O3 -mmx" for ... and so on. > > Think about this for a second. What you are claiming here is that the > output of this bash script can depend upon what CFLAGS bash was built > with: > > #!/bin/bash > echo -e "\x48\x65\x6c\x6c\x6f\x20\x57\x6f\x72\x6c\x64\x21" > > Admittedly a compiler is many orders of magnitude more complex than > this, but functionally the same. Only the code and the options passed > to the compiler can effect its output. Or to put another way, one > could write a C compiler in java, C#, python, or even shell script > that would support the exact same flags as gcc and generate the exact > same code. They would almost certainly be much, much slower, but the > output would be the same. It is identical in concept to changing the > flags that _gcc_ is built with...the gcc program itself changes > (hopefully gets faster), but the output remains the same.
I might be a newbie in terms of this list, but this is completely clear to *me*. Thanks anyway, maybe this helps in getting this to the Howtos, the Wiki, etc. Stefan -- gentoo-user@gentoo.org mailing list
