squash some tolower/toupper conversion warnings

diff --git a/lib/expr/exeval.c b/lib/expr/exeval.c
index 80528263364c160098ce1d4cd6e6f3d36f7d5217..73d5530c3adf3ed2077bd4e91c65c75395f21bef 100644 (file)
--- a/lib/expr/exeval.c
+++ b/lib/expr/exeval.c
@@ -318,21 +318,21 @@ prformat(Sfio_t* sp, void* vp, Sffmt_t* dp)
                        {
                                for (; *s; s++)
                                        if (isupper(*s))
-                                               *s = tolower(*s);
+                                               *s = (char)tolower(*s);
                                        else if (islower(*s))
-                                               *s = toupper(*s);
+                                               *s = (char)toupper(*s);
                        }
                        else if (streq(txt, "lower"))
                        {
                                for (; *s; s++)
                                        if (isupper(*s))
-                                               *s = tolower(*s);
+                                               *s = (char)tolower(*s);
                        }
                        else if (streq(txt, "upper"))
                        {
                                for (; *s; s++)
                                        if (islower(*s))
-                                               *s = toupper(*s);
+                                               *s = (char)toupper(*s);
                        }
                        else if (streq(txt, "variable"))
                        {