From: Marek Polacek Date: Wed, 16 Sep 2020 13:27:29 +0000 (-0400) Subject: preprocessor: Fix ICE with too long line in fmtwarn [PR96935] X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=31dd5cd6344bfbbe122fb512993b128e11236d35;p=gcc.git preprocessor: Fix ICE with too long line in fmtwarn [PR96935] Here we ICE in char_span::subspan because the offset it gets is -1. It's -1 because get_substring_ranges_for_loc gets a location whose column was 0. That only happens in testcases like the attached where we're dealing with extremely long lines (at least 4065 chars it seems). This does happen in practice, though, so it's not just a theoretical problem (e.g. when building the SU2 suite). Fixed by checking that the column get_substring_ranges_for_loc gets is sane, akin to other checks in that function. gcc/ChangeLog: PR preprocessor/96935 * input.c (get_substring_ranges_for_loc): Return if start.column is less than 1. gcc/testsuite/ChangeLog: PR preprocessor/96935 * gcc.dg/format/pr96935.c: New test. --- diff --git a/gcc/input.c b/gcc/input.c index d573b90341a..29d10f06b86 100644 --- a/gcc/input.c +++ b/gcc/input.c @@ -1461,6 +1461,8 @@ get_substring_ranges_for_loc (cpp_reader *pfile, size_t literal_length = finish.column - start.column + 1; /* Ensure that we don't crash if we got the wrong location. */ + if (start.column < 1) + return "zero start column"; if (line.length () < (start.column - 1 + literal_length)) return "line is not wide enough"; diff --git a/gcc/testsuite/gcc.dg/format/pr96935.c b/gcc/testsuite/gcc.dg/format/pr96935.c new file mode 100644 index 00000000000..c31109704be --- /dev/null +++ b/gcc/testsuite/gcc.dg/format/pr96935.c @@ -0,0 +1,9 @@ +/* PR preprocessor/96935 */ +/* { dg-do compile } */ +/* { dg-options "-O" } */ + +void +foo (char const *name) +{ + /* 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*/ __builtin_printf ("%s", name); +}