diff --git a/ChangeLog b/ChangeLog
index 6d7ce74..665054d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2020-11-17  Dmitry V. Levin  <ldv@altlinux.org>
+
+	* config.guess: Combine two heuristics to detect musl libc.
+
 2020-11-07  Ben Elliston  <bje@gnu.org>
 
 	* config.sub, config.guess: Replace backtick `..` substitutions
diff --git a/config.guess b/config.guess
index 0fc11ed..31f610c 100755
--- a/config.guess
+++ b/config.guess
@@ -2,7 +2,7 @@
 # Attempt to guess a canonical system name.
 #   Copyright 1992-2020 Free Software Foundation, Inc.
 
-timestamp='2020-11-07'
+timestamp='2020-11-17'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -138,9 +138,7 @@ UNAME_VERSION=$( (uname -v) 2>/dev/null) || UNAME_VERSION=unknown
 
 case "$UNAME_SYSTEM" in
 Linux|GNU|GNU/*)
-	# If the system lacks a compiler, then just pick glibc.
-	# We could probably try harder.
-	LIBC=gnu
+	LIBC=unknown
 
 	set_cc_for_build
 	cat <<-EOF > "$dummy.c"
@@ -149,16 +147,30 @@ Linux|GNU|GNU/*)
 	LIBC=uclibc
 	#elif defined(__dietlibc__)
 	LIBC=dietlibc
+	#elif defined(__GLIBC__)
+	LIBC=gnu
 	#else
 	#include <stdarg.h>
+	/* First heuristic to detect musl libc.  */
 	#ifdef __DEFINED_va_list
 	LIBC=musl
-	#else
-	LIBC=gnu
 	#endif
 	#endif
 	EOF
 	eval "$($CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^LIBC' | sed 's, ,,g')"
+
+	# Second heuristic to detect musl libc.
+	if [ "$LIBC" = unknown ] &&
+	   command -v ldd >/dev/null &&
+	   ldd --version 2>&1 | grep -q ^musl; then
+		LIBC=musl
+	fi
+
+	# If the system lacks a compiler, then just pick glibc.
+	# We could probably try harder.
+	if [ "$LIBC" = unknown ]; then
+		LIBC=gnu
+	fi
 	;;
 esac
 
diff --git a/config.sub b/config.sub
index c874b7a..e676896 100755
--- a/config.sub
+++ b/config.sub
@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2020 Free Software Foundation, Inc.
 
-timestamp='2020-11-07'
+timestamp='2020-11-17'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by