I have a pro-file:
Qt Code: 
  1. message("This message should be appeared only once!!!")
  2. CONFIG += qt release
  3. SOURCES += src/main.cpp
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I call qmake:
Qt Code: 
  1. set QMAKESPEC=win32-msvc2008
  2. set QTDIR=c:\Qt\4.8.4_vs2008\
  3.  
  4. call "C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\vcvarsall.bat" x86
  5. call "%QTDIR%\bin\qmake.exe" -tp vc Server.pro
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... and I got a very strange output:
Qt Code: 
  1. Setting environment for using Microsoft Visual Studio 2008 x86 tools.
  2. Project MESSAGE: This message should be appeared only once!!!
  3. Project MESSAGE: This message should be appeared only once!!!
  4. Project MESSAGE: This message should be appeared only once!!!
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The question is: why did it process pro file THREE times instead of one?