Output files with different contents

Technical Note 221111






12/12/2022 8:35 AM


his technical note describes how the generated output when building a project can differ from build to build.


Differences in the generated output can occur when you:

  • build with full paths
  • build in another location
  • build using the preprocessor symbols __TIME__ or __DATE__
  • build a library

Building with full paths

For causes of differences in the generated output when building with full paths, see technical note 59374.

Building in another location

Building a project in another location should not affect the output file. For information on differences in the output file when building a project at another location, see technical note 59374.

Building using the preprocessor symbols __TIME__  ,  __DATE__

When building a project, using the preprocessor symbols __TIME__ or __DATE__ will cause the generated output to be different. If these symbols conflict with the need to generate deterministic builds, remove them.

Building a library

The tool iarchive.exe adds Unix timestamps to each library. There is a new timestamp every time a project is built. To avoid this, use the iarchive command line option --fake_time.


To get deterministic builds, you might need to modify the project as suggested in this technical note and in technical note 59374.

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