A macro placed at the end of a file with no newline causes an infinite loop. [Test Kconfig] $(info,hello) \ No newline at end of file I realized that flex-provided input() returns 0 instead of EOF when it reaches the end of a file. Fixes: 104daea149c4 ("kconfig: reference environment variables directly and remove 'option env='") Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> --- scripts/kconfig/lexer.l | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/scripts/kconfig/lexer.l b/scripts/kconfig/lexer.l index f93b535a080c..5f1bc3320307 100644 --- a/scripts/kconfig/lexer.l +++ b/scripts/kconfig/lexer.l @@ -303,8 +303,11 @@ static char *expand_token(const char *in, size_t n) new_string(); append_string(in, n); - /* get the whole line because we do not know the end of token. */ - while ((c = input()) != EOF) { + /* + * get the whole line because we do not know the end of token. + * input() returns 0 (not EOF!) when it reachs the end of file. + */ + while ((c = input()) != 0) { if (c == '\n') { unput(c); break; -- 2.40.1