The compiler enables you to use multiple options even where these might conflict. This
means that you can append new options to an existing command line, for example, in a
makefile or a via file.
Where options override previous options on the same command line, the last option specified
always takes precedence. For example:
armcc -O1 -O2 -Ospace -Otime ...
is executed by the compiler as:
armcc -O2 -Otime
You can use the environment variable
specify compiler command-line options. Options specified on the command line take precedence
over options specified in the environment variable.
To see how the compiler has processed the command line, use the
--show_cmdline option. This shows nondefault options that the compiler
used. The contents of any via files are expanded. In the example used here, although the
armcc -O2 -Otime, the output from
--show_cmdline does not include
-O2. This is because
-O2 is the default optimization level, and
--show_cmdline does not show options that apply by default.