Rollup merge of #107931 - cjgillot:issue-107353, r=WaffleLapkin

Intern span when length is MAX_LEN with parent. Fixes https://github.com/rust-lang/rust/issues/107353
2026-07-18 01:04:42 -04:00 · 2023-02-13 11:34:58 +01:00
parent 8674adc25c 84bb373b2a
commit 3e5c11b855
2 changed files with 15 additions and 1 deletions
@@ -110,11 +110,16 @@ impl Span {
                // Inline format with parent.
                let len_or_tag = len_or_tag | PARENT_MASK;
                let parent2 = parent.local_def_index.as_u32();
-                if ctxt2 == SyntaxContext::root().as_u32() && parent2 <= MAX_CTXT {
+                if ctxt2 == SyntaxContext::root().as_u32()
+                    && parent2 <= MAX_CTXT
+                    && len_or_tag < LEN_TAG
+                {
+                    debug_assert_ne!(len_or_tag, LEN_TAG);
                    return Span { base_or_index: base, len_or_tag, ctxt_or_tag: parent2 as u16 };
                }
            } else {
                // Inline format with ctxt.
+                debug_assert_ne!(len_or_tag, LEN_TAG);
                return Span {
                    base_or_index: base,
                    len_or_tag: len as u16,