[gcc/devel/rust/master] Fix nullptr when resolving the root of a path expression

[gcc/devel/rust/master] Fix nullptr when resolving the root of a path expression

[Thomas Schwinge]

https://gcc.gnu.org/g:1d19dd8a691fd3fcc6214e99d9da5bc9fcb1c122

commit 1d19dd8a691fd3fcc6214e99d9da5bc9fcb1c122
Author: Philip Herron <philip.herron@embecosm.com>
Date:   Mon Apr 25 17:57:24 2022 +0100

    Fix nullptr when resolving the root of a path expression
    
    When we resolve paths we don't have a _type_, in this senario there is a
    bug in our resolution of this generic function so this means the root_tyty
    is nullptr but the offset is non zero so we return nullptr.
    
    Addresses #1132

Diff:
---
 gcc/rust/typecheck/rust-hir-type-check-path.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/rust/typecheck/rust-hir-type-check-path.cc b/gcc/rust/typecheck/rust-hir-type-check-path.cc
index e2fa7f5e9ac..530f630d5ec 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-path.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-path.cc
@@ -178,7 +178,7 @@ TypeCheckExpr::resolve_root_path (HIR::PathInExpression &expr, size_t *offset,
       HIR::PathExprSegment &seg = expr.get_segments ().at (i);
 
       bool have_more_segments = (expr.get_num_segments () - 1 != i);
-      bool is_root = *offset == 0;
+      bool is_root = *offset == 0 || root_tyty == nullptr;
       NodeId ast_node_id = seg.get_mappings ().get_nodeid ();
 
       // then lookup the reference_node_id