BUG: Fix #7969. Fix moc output files if source dir contains regex characters.

Modules/FindQt4.cmake

@@ -855,12 +855,14 @@ IF (QT4_QMAKE_FOUND)
     SET(_checkinfile ${CMAKE_CURRENT_SOURCE_DIR})
     IF(_infileLength GREATER _binlength)
       STRING(SUBSTRING "${infile}" 0 ${_binlength} _checkinfile)
-    ENDIF(_infileLength GREATER _binlength)
-    IF(CMAKE_CURRENT_BINARY_DIR MATCHES "${_checkinfile}")
-      FILE(RELATIVE_PATH rel ${CMAKE_CURRENT_BINARY_DIR} ${infile})
-    ELSE(CMAKE_CURRENT_BINARY_DIR MATCHES "${_checkinfile}")
+      IF(_checkinfile STREQUAL "${CMAKE_CURRENT_BINARY_DIR}")
+        FILE(RELATIVE_PATH rel ${CMAKE_CURRENT_BINARY_DIR} ${infile})
+      ELSE(_checkinfile STREQUAL "${CMAKE_CURRENT_BINARY_DIR}")
+        FILE(RELATIVE_PATH rel ${CMAKE_CURRENT_SOURCE_DIR} ${infile})
+      ENDIF(_checkinfile STREQUAL "${CMAKE_CURRENT_BINARY_DIR}")
+    ELSE(_infileLength GREATER _binlength)
       FILE(RELATIVE_PATH rel ${CMAKE_CURRENT_SOURCE_DIR} ${infile})
-    ENDIF(CMAKE_CURRENT_BINARY_DIR MATCHES "${_checkinfile}")
+    ENDIF(_infileLength GREATER _binlength)
     SET(_outfile "${CMAKE_CURRENT_BINARY_DIR}/${rel}")
     STRING(REPLACE ".." "__" _outfile ${_outfile})
     GET_FILENAME_COMPONENT(outpath ${_outfile} PATH)