Compiler User GuideConventions and Feedback Overview of the Compiler Getting Started with the Compiler Compiler command-line syntax Compiler command-line options listed by group Default compiler behavior Order of compiler command-line options Using stdin to input source code to the compiler Directing output to stdout Filename suffixes recognized by the compiler Compiler output files Factors influencing how the compiler searches for Compiler command-line options and search paths Compiler search rules and the current place The ARMCCnINC environment variable Code compatibility between separately compiled and Linker feedback during compilation Unused function code Minimizing code size by eliminating unused functio Minimizing code size by reducing compilation requi Compilation build time How to minimize compilation build time Minimizing compilation build time with a single ar Effect of --multifile on compilation build time Minimizing compilation build time with parallel ma Compilation build time and operating system choice Compiler Features Compiler Coding Practices Compiler Diagnostic Messages Using the Inline and Embedded Assemblers of the AR
Compiler User Guide
Order of compiler command-line options
In general, compiler 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
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 -O3 -Ospace -Otime ...
is executed by the compiler as:
armcc -O3 -Otime
The environment variable
To see how the compiler has processed the command line, use