From 1080621ae2d5ad29fefc44c5fe97ff7c18ad96ce Mon Sep 17 00:00:00 2001
From: Karl Williamson <khw@cpan.org>
Date: Thu, 24 Dec 2020 20:25:00 -0700
Subject: [PATCH] XXX pp.c: do %g print under mutex,

---
 pp.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/pp.c b/pp.c
index 68b4e461562d..bb97fc8c8aaa 100644
--- a/pp.c
+++ b/pp.c
@@ -2879,10 +2879,16 @@ PP(pp_sin)
 #if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
 	      ! Perl_isnan(value) &&
 #endif
-	      (op_type == OP_LOG ? (value <= 0.0) : (value < 0.0))) {
+	      (op_type == OP_LOG ? (value <= 0.0) : (value < 0.0)))
+          {
+              char * mesg;
+              SETLOCALE_LOCK;
 	      SET_NUMERIC_STANDARD();
+              mesg = Perl_form(aTHX_ "Can't take %s of %" NVgf, neg_report, value);
+              SETLOCALE_UNLOCK;
+
 	      /* diag_listed_as: Can't take log of %g */
-	      DIE(aTHX_ "Can't take %s of %" NVgf, neg_report, value);
+	      DIE(aTHX_ "%s", mesg);
 	  }
       }
       switch (op_type) {