message: Make file argument an absolute path
diff: @@ -85,7 +85,8 @@ if(RANGE_V3_HEADER_CHECKS)
  # Deprecated headers
  if(CMAKE_CXX_COMPILER_ID STREQUAL GNU)
  foreach(header "${RANGE_V3_PUBLIC_HEADERS}")
  - file(STRINGS "${header}" is_deprecated LIMIT_COUNT 1
  + file(STRINGS "${CMAKE_CURRENT_SOURCE_DIR}/include/${header}" is_deprecated
  + LIMIT_COUNT 1
  REGEX ".*RANGES_DEPRECATED_HEADER.*")
  if(is_deprecated)
  list(APPEND RANGE_V3_DEPRECATED_PUBLIC_HEADERS "${header}")
  