From: Ville Voutilainen <ville.voutilainen@gmail.com>
Date: Thu, 15 May 2025 13:26:52 +0000 (+0300)
Subject: Further simplify the stdlib inline folding
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fa365450352ae5cc7c0078e37e641341fb48e6b6;p=thirdparty%2Fgcc.git

Further simplify the stdlib inline folding

gcc/cp/ChangeLog:
	* cp-gimplify.cc (cp_fold): Do the conversion unconditionally, even for same-type cases.

gcc/ChangeLog:
	* doc/invoke.texi: Add to_underlying to -ffold-simple-inlines.
---

diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc
index eab55504b05..f7bd453bc5e 100644
--- a/gcc/cp/cp-gimplify.cc
+++ b/gcc/cp/cp-gimplify.cc
@@ -3347,8 +3347,7 @@ cp_fold (tree x, fold_flags_t flags)
 		|| id_equal (DECL_NAME (callee), "as_const")))
 	  {
 	    r = CALL_EXPR_ARG (x, 0);
-	    if (!same_type_p (TREE_TYPE (x), TREE_TYPE (r)))
-	      r = build_nop (TREE_TYPE (x), r);
+	    r = build_nop (TREE_TYPE (x), r);
 	    x = cp_fold (r, flags);
 	    break;
 	  }
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index ee7180110e1..83c63ce6ae5 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -3348,7 +3348,8 @@ aliases, the default is @option{-fno-extern-tls-init}.
 @item -ffold-simple-inlines
 @itemx -fno-fold-simple-inlines
 Permit the C++ frontend to fold calls to @code{std::move}, @code{std::forward},
-@code{std::addressof} and @code{std::as_const}.  In contrast to inlining, this
+@code{std::addressof}, @code{std::to_underlying}
+and @code{std::as_const}.  In contrast to inlining, this
 means no debug information will be generated for such calls.  Since these
 functions are rarely interesting to debug, this flag is enabled by default
 unless @option{-fno-inline} is active.