On Fedora 9, Qt 4.5.2's qmake seems not to like including a very large .pri file with very many SOURCES/HEADERS. After including it, stange behaviour appears. In particular the system() calls no longer get executed.

Contents of files.pri (cut):

Qt Code: 
  1. # ==================================================
  2. # This file has been automatically generated.
  3. # Please do not edit.
  4. # ==================================================
  5. GEN_HEADERS += path_to\src\generated\headerx.h
  6. GEN_SOURCES += path_to\src\generated\sourcex.cpp
  7. ... 
  8. [620 headers + 620 sources]
  9.  
  10. HEADERS += $$GEN_HEADERS
  11. SOURCES += $$GEN_SOURCES
  12. QMAKE_CLEAN += $$GEN_HEADERS
  13. QMAKE_CLEAN += $$GEN_SOURCES
  14. QMAKE_DISTCLEAN +=path_to\src\generated\files.pri
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On Windows, and on Fedora 10 and 11, this still works.

However, I wonder whether they just have a larger limit, or if they have no (practical) limit?