From: Martin Sebor <msebor@redhat.com>
Date: Mon, 8 Jun 2020 15:06:48 +0000 (-0600)
Subject: PR bootstrap/95555 - powepc64 bootstrap failure due to -Wmaybe-uninitialized in reloa... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=c1057cc0a8ad972e0a2218ab74038a56e5514c39;p=gcc.git

PR bootstrap/95555 - powepc64 bootstrap failure due to -Wmaybe-uninitialized in reload_cse_simplify_operands

gcc/ChangeLog:

	* postreload.c (reload_cse_simplify_operands): Clear first array element
	before using it.  Assert a precondition.
---

diff --git a/gcc/postreload.c b/gcc/postreload.c
index f6258285022..c9e637500f1 100644
--- a/gcc/postreload.c
+++ b/gcc/postreload.c
@@ -592,6 +592,13 @@ reload_cse_simplify_operands (rtx_insn *insn, rtx testreg)
 	}
     }
 
+  /* The loop below sets alternative_order[0] but -Wmaybe-uninitialized
+     can't know that.  Clear it here to avoid the warning.  */
+  alternative_order[0] = 0;
+  gcc_assert (!recog_data.n_alternatives
+	      || (which_alternative >= 0
+		  && which_alternative < recog_data.n_alternatives));
+
   /* Record all alternatives which are better or equal to the currently
      matching one in the alternative_order array.  */
   for (i = j = 0; i < recog_data.n_alternatives; i++)