diff --git a/src/timezone/README b/src/timezone/README
index 10aeedce92..f588d1f5ad 100644
--- a/src/timezone/README
+++ b/src/timezone/README
@@ -55,7 +55,7 @@ match properly on the old version.
 Time Zone code
 ==============
 
-The code in this directory is currently synced with tzcode release 2020c.
+The code in this directory is currently synced with tzcode release 2020d.
 There are many cosmetic (and not so cosmetic) differences from the
 original tzcode library, but diffs in the upstream version should usually
 be propagated to our version.  Here are some notes about that.
diff --git a/src/timezone/zic.c b/src/timezone/zic.c
index a1c64051f7..0ea6ead2db 100644
--- a/src/timezone/zic.c
+++ b/src/timezone/zic.c
@@ -634,7 +634,8 @@ static const char *leapsec;
 static const char *tzdefault;
 
 /* -1 if the TZif output file should be slim, 0 if default, 1 if the
-   output should be fat for backward compatibility.  The default is slim.  */
+   output should be fat for backward compatibility.  ZIC_BLOAT_DEFAULT
+   determines the default.  */
 static int	bloat;
 
 static bool
@@ -787,7 +788,16 @@ main(int argc, char **argv)
 	if (optind == argc - 1 && strcmp(argv[optind], "=") == 0)
 		usage(stderr, EXIT_FAILURE);	/* usage message by request */
 	if (bloat == 0)
-		bloat = strcmp(ZIC_BLOAT_DEFAULT, "slim") == 0 ? -1 : 1;
+	{
+		static char const bloat_default[] = ZIC_BLOAT_DEFAULT;
+
+		if (strcmp(bloat_default, "slim") == 0)
+			bloat = -1;
+		else if (strcmp(bloat_default, "fat") == 0)
+			bloat = 1;
+		else
+			abort();			/* Configuration error.  */
+	}
 	if (directory == NULL)
 		directory = "data";
 	if (tzdefault == NULL)