cleaning up unittest build

unittests/testcfg/rtems/cmake/Platform/a72_lp64_qemu.cmake

@@ -1,3 +1,3 @@
-add_compile_options("-mcpu=cortex-a72" "-I/opt/rtems/6/aarch64-rtems6/a72_lp64_qemu/lib/include" "-I${CMAKE_SOURCE_DIR}/unittests/testcfg/rtems/include")
+add_compile_options("-mcpu=cortex-a72" "-I/opt/rtems/6/aarch64-rtems6/a72_lp64_qemu/lib/include")
 
 add_link_options("-B/opt/rtems/6/aarch64-rtems6/a72_lp64_qemu/lib" "-qrtems")

unittests/testcfg/rtems/cmake/aarch64-rtems6-toolchain.cmake

@@ -1,4 +1,4 @@
-# the name of the target operating system
+## the name of the target operating system
 set(CMAKE_SYSTEM_NAME a72_lp64_qemu)
 
 set(CMAKE_SYSTEM_PROCESSOR a72)
@@ -7,19 +7,30 @@ set(CMAKE_SYSTEM_PROCESSOR a72)
 set(CMAKE_C_COMPILER   aarch64-rtems6-gcc)
 set(CMAKE_CXX_COMPILER aarch64-rtems6-g++)
 
+# built in tests fail
 set(CMAKE_C_COMPILER_WORKS 1)
 set(CMAKE_CXX_COMPILER_WORKS 1)
 
 # adjust the default behavior of the FIND_XXX() commands:
 # search programs in the host environment
-set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
 
 # search headers and libraries in the target environment
 set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
 set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
+
+# ignore host installed libraries
+# makes find_package() ignore the <package>Config.cmake files
+set(CMAKE_IGNORE_PATH /usr/local)
+
 
 # supress errors
 add_compile_definitions("__STDC_VERSION__")
 
+# make newlib behave like glib with an intercepted cmath
+add_compile_options("-I${CMAKE_SOURCE_DIR}/unittests/testcfg/rtems/include")
+
+# we supply an a72_lp64_qemu.cmake there
 list(APPEND CMAKE_MODULE_PATH
      "${CMAKE_CURRENT_SOURCE_DIR}/unittests/testcfg/rtems/cmake")