Index: cmake/base-config-ix.cmake
===================================================================
--- cmake/base-config-ix.cmake
+++ cmake/base-config-ix.cmake
@@ -148,7 +148,14 @@
         endif()
       endif()
     elseif("${COMPILER_RT_DEFAULT_TARGET_ARCH}" MATCHES "powerpc")
+      # Strip out -nodefaultlibs when calling TEST_BIG_ENDIAN. Configuration
+      # will fail with this option when building with a sanitizer.
+      set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
+      string(REPLACE "-nodefaultlibs" "" CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
       TEST_BIG_ENDIAN(HOST_IS_BIG_ENDIAN)
+      # Undo the change.
+      set(CMAKE_REQUIRED_FLAGS "${OLD_CMAKE_REQUIRED_FLAGS}")
+
       if(HOST_IS_BIG_ENDIAN)
         test_target_arch(powerpc64 "" "-m64")
       else()