diff --git a/pycparser/c_lexer.py b/pycparser/c_lexer.py
index 4f66b244..53ac4383 100644
--- a/pycparser/c_lexer.py
+++ b/pycparser/c_lexer.py
@@ -278,7 +278,11 @@ def success(pp_line: Optional[str], pp_filename: Optional[str]) -> None:
             if pp_line is None:
                 self._error("line number missing in #line", self._pos + line_len)
             else:
-                self._lineno = int(pp_line)
+                try:
+                    self._lineno = int(pp_line)
+                except ValueError:
+                    self._error("invalid #line directive", self._pos + line_len)
+                    return
                 if pp_filename is not None:
                     self._filename = pp_filename
             self._pos = line_end + 1
diff --git a/tests/test_c_lexer.py b/tests/test_c_lexer.py
index 00acddcd..01bc2c2c 100644
--- a/tests/test_c_lexer.py
+++ b/tests/test_c_lexer.py
@@ -572,6 +572,10 @@ def test_preprocessor(self):
         self.assertLexerError('#line "ka"', ERR_FILENAME_BEFORE_LINE)
         self.assertLexerError("#line df", ERR_INVALID_LINE_DIRECTIVE)
         self.assertLexerError("#line \n", ERR_LINENUM_MISSING)
+        # Integer suffixes are not valid in #line directives (issue #587).
+        self.assertLexerError("#line 0u", ERR_INVALID_LINE_DIRECTIVE)
+        self.assertLexerError("#line 1U", ERR_INVALID_LINE_DIRECTIVE)
+        self.assertLexerError("#line 10uLL", ERR_INVALID_LINE_DIRECTIVE)
         # a compatible preprocessor must remove comments.
         self.assertLexerError("//", ERR_COMMENT)
         self.assertLexerError("/*", ERR_COMMENT)