ARM Compiler toolchain v4.1 for µVision Using the Compiler

Getting started with the Compiler
3.11 Compiler search rules and the current place
By default, the compiler uses Berkeley UNIX search rules, so source files and #include header
files are searched for relative to the current place. The current place is the directory containing
the source or header file currently being processed by the compiler.
When a file is found relative to an element of the search path, the directory containing that file
becomes the new current place. When the compiler has finished processing that file, it restores
the previous current place. At each instant there is a stack of current places corresponding to the
stack of nested #include directives. For example, if the current place is the include directory
...\include, and the compiler is seeking the include file sys\defs.h, it locates
...\include\sys\defs.h if it exists. When the compiler begins to process defs.h, the current
place becomes ...\include\sys. Any file included by defs.h that is not specified with an
absolute path name, is searched for relative to ...\include\sys.
The original current place ...\include is restored only when the compiler has finished
processing defs.h.
You can disable the stacking of current places by using the compiler option --kandr_include.
This option makes the compiler use Kernighan and Ritchie search rules whereby each nonrooted
user #include is searched for relative to the directory containing the source file that is being
compiled.
3.11.1 See also
Concepts
• Factors influencing how the compiler searches for header files on page 3-17.
Reference
• --kandr_include on page 3-55.
Other information
• Kernighan, B.W. and Ritchie, D.M., The C Programming Language (2nd edition, 1988).
Prentice-Hall, Englewood Cliffs, NJ, USA. ISBN 0-13-110362-8.
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