Bad PCH usage detected
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Pre-compiled headers
WARNING: Bad PCH usage detected, .\MyFile.cpp will not be instrumented.This error is caused by the use of pre-compiled headers in a Microsoft VS build. The use of PCH interferes with Insure++'s ability to properly instrument your code so this warning message is shown.
To solve it you simply need to turn off the use of pre-compiled headers, build clean and then rebuild with Insure++.
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"Warning: Bad PCH usage" occurs when somebody tries to use a precompiled header before it has been built. e.g:
> insure -Yustdafx.h foo.cpp
before doing this:
> insure -Ycstdafx.h stdafx.cpp
will cause the driver to spit out that message. There are other situations that will also cause this message, such as the following:
> insure -Ycstdafx.h stdafx.cpp
> cl -Ycstdafx.h stdafx.cpp
> insure -Yustdafx.h foo.cpp # instrumented pch is now out of date
PR40798 documents the reason for this. In brief, it is to handle silly users who mix Insure++ pch builds and normal pch builds willy-nilly.
Disabling PCH will cause the warning message to go away, but it should not be necessary. Users should be aware that rebuilding the PCH without Insure++ will cause Insure++ to treat it's own instrumented precompiled header as out of date. To avoid this, always build the instrumented precompiled header before using it, and do not build a non-instrumented precompiled header before attempting to use an instrumented one without also building an instrumented precompiled header.
If you find this confusing, the best thing you can do is have a separate configuration for Insure++ builds and normal Debug builds. This will help avoid building instrumented stdafx.pch and uninstrumented stdafx.pch willy-nilly.
When in doubt, turn pch off, but make sure the project is able to build normally without using PCH before complaining that the project doesn't build under Insure++ when PCH is turned off. Some broken projects will only build if PCH is turned on. Such projects are usually just poorly configured and should be fixed anyway, IMO.