diff --git a/lib/libc/locale/cXXrtomb_iconv.h b/lib/libc/locale/cXXrtomb_iconv.h
--- a/lib/libc/locale/cXXrtomb_iconv.h
+++ b/lib/libc/locale/cXXrtomb_iconv.h
@@ -75,7 +75,7 @@
 			errno = EINVAL;
 			return (-1);
 		}
-		handle->cv_shared->ci_discard_ilseq = true;
+		handle->cv_shared->ci_discard_ilseq = false;
 		handle->cv_shared->ci_hooks = NULL;
 		cs->srcbuf_len = 0;
 		cs->initialized = true;
@@ -92,7 +92,7 @@
 	dst = s;
 	dstleft = MB_CUR_MAX_L(locale);
 	err = _citrus_iconv_convert(handle, &src, &srcleft, &dst, &dstleft,
-	    0, &invlen);
+	    _CITRUS_ICONV_F_HIDE_INVALID, &invlen);
 
 	/* Character is part of a surrogate pair. We need more input. */
 	if (err == EINVAL)
diff --git a/lib/libc/locale/mbrtocXX_iconv.h b/lib/libc/locale/mbrtocXX_iconv.h
--- a/lib/libc/locale/mbrtocXX_iconv.h
+++ b/lib/libc/locale/mbrtocXX_iconv.h
@@ -78,7 +78,7 @@
 			errno = EINVAL;
 			return (-1);
 		}
-		handle->cv_shared->ci_discard_ilseq = true;
+		handle->cv_shared->ci_discard_ilseq = false;
 		handle->cv_shared->ci_hooks = NULL;
 		cs->srcbuf_len = cs->dstbuf_len = 0;
 		cs->initialized = true;
@@ -110,7 +110,7 @@
 		assert(srcleft <= sizeof(cs->srcbuf) &&
 		    dstleft <= sizeof(cs->dstbuf.bytes));
 		err = _citrus_iconv_convert(handle, &src, &srcleft,
-		    &dst, &dstleft, 0, &invlen);
+		    &dst, &dstleft, _CITRUS_ICONV_F_HIDE_INVALID, &invlen);
 		cs->dstbuf_len = (dst - cs->dstbuf.bytes) / sizeof(charXX_t);
 
 		/* Got new character(s). Return the first. */