Use execute_process instead of deprecated exec_program, and doesn't use unnecessary IS_SYMLINK.

CMakeModules/cmake_uninstall.cmake.in

@@ -6,16 +6,16 @@ file(READ "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt" files)
 string(REGEX REPLACE "\n" ";" files "${files}")
 foreach(file ${files})
   message(STATUS "Uninstalling $ENV{DESTDIR}${file}")
-  if(IS_SYMLINK "$ENV{DESTDIR}${file}" OR EXISTS "$ENV{DESTDIR}${file}")
-    exec_program(
-      "@CMAKE_COMMAND@" ARGS "-E remove \"$ENV{DESTDIR}${file}\""
+  if(EXISTS "$ENV{DESTDIR}${file}")
+    execute_process(
+      COMMAND @CMAKE_COMMAND@ -E remove "$ENV{DESTDIR}${file}"
       OUTPUT_VARIABLE rm_out
-      RETURN_VALUE rm_retval
+      RESULT_VARIABLE rm_retval
       )
     if(NOT "${rm_retval}" STREQUAL 0)
       message(FATAL_ERROR "Problem when removing $ENV{DESTDIR}${file}")
     endif(NOT "${rm_retval}" STREQUAL 0)
-  else(IS_SYMLINK "$ENV{DESTDIR}${file}" OR EXISTS "$ENV{DESTDIR}${file}")
+  else(EXISTS "$ENV{DESTDIR}${file}")
     message(STATUS "File $ENV{DESTDIR}${file} does not exist.")
-  endif(IS_SYMLINK "$ENV{DESTDIR}${file}" OR EXISTS "$ENV{DESTDIR}${file}")
+  endif(EXISTS "$ENV{DESTDIR}${file}")
 endforeach(file)