[PATCH 1/2] dfa: attempt to pacify Coverity

[Paul Eggert]

* lib/dfa.c (lex): Use ‘assume’ rather than ‘abort’,
to try to pacify Coverity.
(maybe_disable_superset_dfa): Use ‘assume’ here too, for consistency.
Using ‘assume’ should make the code a tiny bit faster, though
at the cost of having undefined behavior instead of nicely aborting.
---
 ChangeLog | 9 +++++++++
 lib/dfa.c | 5 ++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a138378822..997f51f3b5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2024-05-20  Paul Eggert  <egg...@cs.ucla.edu>
+
+       dfa: attempt to pacify Coverity
+       * lib/dfa.c (lex): Use ‘assume’ rather than ‘abort’,
+       to try to pacify Coverity.
+       (maybe_disable_superset_dfa): Use ‘assume’ here too, for consistency.
+       Using ‘assume’ should make the code a tiny bit faster, though
+       at the cost of having undefined behavior instead of nicely aborting.
+
 2024-05-20  Bruno Haible  <br...@clisp.org>
 
        Make it easy to generate debug info for libbacktrace on macOS.
diff --git a/lib/dfa.c b/lib/dfa.c
index c79afddcd9..0ccb167176 100644
--- a/lib/dfa.c
+++ b/lib/dfa.c
@@ -1221,8 +1221,7 @@ lex (struct dfa *dfa)
     {
       /* This loop should consume at most a backslash and some other
          character.  */
-      if (2 <= i)
-        abort ();
+      assume (i < 2);
 
       if (! dfa->lex.left)
         return dfa->lex.lasttok = END;
@@ -3727,7 +3726,7 @@ maybe_disable_superset_dfa (struct dfa *d)
         {
         case ANYCHAR:
           /* Lowered.  */
-          abort ();
+          assume (false);
         case BACKREF:
           have_backref = true;
           break;
-- 
2.40.1