[gcc r14-8044] gccrs: Fix path expr segment parsing with generic path

[gcc r14-8044] gccrs: Fix path expr segment parsing with generic path

[Arthur Cohen]

https://gcc.gnu.org/g:061c5d2e24831e520c2deaa383c7ba2041e89146

commit r14-8044-g061c5d2e24831e520c2deaa383c7ba2041e89146
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Tue Oct 10 10:04:57 2023 +0200

    gccrs: Fix path expr segment parsing with generic path
    
    When a token was identified as bit left shift it slipped through the
    parser and resulted in an error.
    
    gcc/rust/ChangeLog:
    
            * parse/rust-parse-impl.h (Parser::parse_path_expr_segment): Accept
            left shift tokens in order to let generic parsing function split the
            token.
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 gcc/rust/parse/rust-parse-impl.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gcc/rust/parse/rust-parse-impl.h b/gcc/rust/parse/rust-parse-impl.h
index 8c04a1af175..dde3d63201e 100644
--- a/gcc/rust/parse/rust-parse-impl.h
+++ b/gcc/rust/parse/rust-parse-impl.h
@@ -6808,11 +6808,13 @@ Parser<ManagedTokenSource>::parse_path_expr_segment ()
   /* use lookahead to determine if they actually exist (don't want to
    * accidently parse over next ident segment) */
   if (lexer.peek_token ()->get_id () == SCOPE_RESOLUTION
-      && lexer.peek_token (1)->get_id () == LEFT_ANGLE)
+      && (lexer.peek_token (1)->get_id () == LEFT_ANGLE
+	  || lexer.peek_token (1)->get_id () == LEFT_SHIFT))
     {
       // skip scope resolution
       lexer.skip_token ();
 
+      // Let parse_path_generic_args split "<<" tokens
       AST::GenericArgs generic_args = parse_path_generic_args ();
 
       return AST::PathExprSegment (std::move (ident), locus,