Decreasing build time

Technical Note 48554






11/6/2015 1:05 PM


For large projects, long build times can be a problem.

Solution hints

  1. Enable Parallel Build (Tools > Options > Project > Enable parallel build). On a multi-core computer, this leads to reduced build times. Note: This option is not available in older IAR Embedded Workbench releases.

  2. Make sure to use guard conditions in ALL header files. That is...
    #ifndef __HFILE_H
    #define __HFILE_H
    /* ... */
    .. and also check if it is possible to reduce the number of #includes in some of the source files. This could have great impact on build speed.

    To see the size of each C-file with header files included, enable: Options > C/C++ Compiler > Preprocessor > "Preprocessor output to file". Then check the generated .i-file. Is it large?

  3. Create pre-built libraries of "support"-code (BSPs, stacks etc) that does not have to be re-built with every modification of the application code.

  4. Disable the generation of compiler list files (Options > C/C++ Compiler > List).

  5. If some source files are located on a network drive (even if it is a RAM disk on the server), try copying the files to a "local" drive, and build there. If it goes faster, there might be a network filesystem (NFS/Samba) problem.

  6. If step 5 above helped (use a local drive), it may help to only place Object files and List files on a local drive. Modify Project > Options > General Options > Output. Configure "Object files" and "List files" to be placed locally.

  7. (General hints): See technical note 40547.

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