bug fix:

- revert tbb changes
- unset(freeimage_FOUND CACHE)
- unset(tinyxml_FOUND CACHE)
- set(Simbody_LIBRARIES ${Simbody_STATIC_LIBRARIES}) when ${Simbody_LIBRARIES} not found. this is static build case

cmake/FindFreeimage.cmake

@@ -10,6 +10,8 @@ if (PKG_CONFIG_FOUND)
   endif (NOT freeimage_FOUND)
 endif (PKG_CONFIG_FOUND)
 if (NOT freeimage_FOUND)
+  # Workaround for CMake bug https://gitlab.kitware.com/cmake/cmake/issues/17135
+  unset(freeimage_FOUND CACHE)
   find_package(freeimage CONFIG)
   if (freeimage_FOUND)
     set(freeimage_LIBRARIES freeimage::FreeImage)

cmake/SearchForStuff.cmake

@@ -166,9 +166,9 @@ if (PKG_CONFIG_FOUND)
   #list(APPEND CMAKE_MODULE_PATH ${SimTK_INSTALL_PREFIX}/share/cmake)
   find_package(Simbody)
   if (Simbody_FOUND)  
-    # When simbody is found but it don't define any libs, we should manually define the libs.
+    # When simbody is found but it static libs, we need to add it manually.
     if ("${Simbody_LIBRARIES}" STREQUAL "" OR "${Simbody_LIBRARIES}" STREQUAL "Simbody_LIBRARIES-NOTFOUND")
-      set(Simbody_LIBRARIES SimTKmath SimTKcommon SimTKsimbody)
+    set(Simbody_LIBRARIES ${Simbody_STATIC_LIBRARIES}),  
     endif()
     set (HAVE_SIMBODY TRUE)
   else()
@@ -218,6 +218,8 @@ if (PKG_CONFIG_FOUND)
     message (STATUS "Using system tinyxml.")
     pkg_check_modules(tinyxml tinyxml)
     if (NOT tinyxml_FOUND)
+      # Workaround for CMake bug https://gitlab.kitware.com/cmake/cmake/issues/17135
+      unset(tinyxml_FOUND CACHE)
       find_package(tinyxml CONFIG)
       if (tinyxml_FOUND)
         message (STATUS "tinyxml found via find_package")
@@ -336,16 +338,10 @@ if (PKG_CONFIG_FOUND)
 
   #################################################
   # Find TBB
-  find_package(TBB CONFIG REQUIRED)
-  if (TBB_FOUND)
-    set(TBB_LIBRARIES TBB::tbb TBB::tbbmalloc)
-    message (STATUS "TBB version: " ${TBB_VERSION})
-  endif()
-  if (NOT TBB_FOUND)
-    pkg_check_modules(TBB tbb)
-  endif()
+  pkg_check_modules(TBB tbb)
   set (TBB_PKG_CONFIG "tbb")
   if (NOT TBB_FOUND)
+
     message(STATUS "TBB not found, attempting to detect manually")
     set (TBB_PKG_CONFIG "")