Ordering command-line options

In general, command‑line options can appear in any order in a single compiler invocation. However, the effects of some options depend on the order they appear in the command line and how they are combined with other related options, for example, optimization options prefixed by ‑O, or PCH options. See Precompiled header files.

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 make file or via file.

Where options override previous options on the same command line, the last one found always takes precedence. For example:

armcc ‑O1 ‑O2 ‑Ospace ‑Otime ...

is executed by the compiler as:

armcc ‑O2 ‑Otime

To see how the compiler has processed the command line, use the ‑‑show_cmdline option. The commands are shown normalized, and the contents of any via files are expanded.