You can specify options by setting the CCFLAGS variable.
The CCFLAGS variable can be used explicitly in the command line. The following example shows how to set CCFLAGS (C Shell):
example% setenv CCFLAGS ’-xO2 -m64’
The next example uses CCFLAGS explicitly.
example% CC $CCFLAGS any.cc
When you use make, if the CCFLAGS variable is set as in the preceding example and the makefile’s compilation rules are implicit, then invoking make will result in a compilation equivalent to the following command:
CC -xO2 -m64 files...