compile.c: default_len is positive

Recent GCC warns that default_len can be negative (thus can
overflow PTRDIFF_MAX), which is a false assert.  Suppresses
warnings by adding __builtin_unreachable.

See also: https://travis-ci.org/ruby/ruby/jobs/443568193#L2227


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65167 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 0 deletions

diff --git a/compile.c b/compile.c
index 2a4680476b..272b9ddacc 100644
--- a/compile.c
+++ b/compile.c
@@ -8083,6 +8083,9 @@ iseq_build_kw(rb_iseq_t *iseq, VALUE params, VALUE keywords)
 	keyword->table = ids;
 	return keyword;
     }
+    else if (default_len < 0) {
+        UNREACHABLE;
+    }
 
     dvs = ALLOC_N(VALUE, (unsigned int)default_len);