Andrew Morrow: Among the various libc++ tests that currently don't pass on Linux are
localization/locale.categories/category.collate/category.ctype/locale.ctype.byname/is_1.pass.cpp
and scan_is.pass.cpp. The tests fail when the character class being
tested is compound, like ctype_base::alnum or ctype_base::graph,
because the existing series of conditionals in do_is an do_scan_is
will abort too early. For instance, if the character class being
tested is alnum, and the character is numeric, do_is will return false
because iswalpha_l will return false, 'result' becomes false, and the
'true' result from the later call to iswdigit_l ends up being ignored
. A similar problem exists in do_scan_is.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@161192 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/src/locale.cpp b/src/locale.cpp
index fe99488..854fd23 100644
--- a/src/locale.cpp
+++ b/src/locale.cpp
@@ -1052,17 +1052,17 @@
 #ifdef _LIBCPP_WCTYPE_IS_MASK
     return static_cast<bool>(iswctype_l(c, m, __l));
 #else
-    bool result = true;
-    if (m & space && !iswspace_l(c, __l)) result = false;
-    if (m & print && !iswprint_l(c, __l)) result = false;
-    if (m & cntrl && !iswcntrl_l(c, __l)) result = false;
-    if (m & upper && !iswupper_l(c, __l)) result = false;
-    if (m & lower && !iswlower_l(c, __l)) result = false;
-    if (m & alpha && !iswalpha_l(c, __l)) result = false;
-    if (m & digit && !iswdigit_l(c, __l)) result = false;
-    if (m & punct && !iswpunct_l(c, __l)) result = false;
-    if (m & xdigit && !iswxdigit_l(c, __l)) result = false;
-    if (m & blank && !iswblank_l(c, __l)) result = false;
+    bool result = false;
+    if (m & space) result |= (iswspace_l(c, __l) != 0);
+    if (m & print) result |= (iswprint_l(c, __l) != 0);
+    if (m & cntrl) result |= (iswcntrl_l(c, __l) != 0);
+    if (m & upper) result |= (iswupper_l(c, __l) != 0);
+    if (m & lower) result |= (iswlower_l(c, __l) != 0);
+    if (m & alpha) result |= (iswalpha_l(c, __l) != 0);
+    if (m & digit) result |= (iswdigit_l(c, __l) != 0);
+    if (m & punct) result |= (iswpunct_l(c, __l) != 0);
+    if (m & xdigit) result |= (iswxdigit_l(c, __l) != 0);
+    if (m & blank) result |= (iswblank_l(c, __l) != 0);
     return result;
 #endif
 }
@@ -1109,17 +1109,16 @@
         if (iswctype_l(*low, m, __l))
             break;
 #else
-        if (m & space && !iswspace_l(*low, __l)) continue;
-        if (m & print && !iswprint_l(*low, __l)) continue;
-        if (m & cntrl && !iswcntrl_l(*low, __l)) continue;
-        if (m & upper && !iswupper_l(*low, __l)) continue;
-        if (m & lower && !iswlower_l(*low, __l)) continue;
-        if (m & alpha && !iswalpha_l(*low, __l)) continue;
-        if (m & digit && !iswdigit_l(*low, __l)) continue;
-        if (m & punct && !iswpunct_l(*low, __l)) continue;
-        if (m & xdigit && !iswxdigit_l(*low, __l)) continue;
-        if (m & blank && !iswblank_l(*low, __l)) continue;
-        break;
+        if (m & space && iswspace_l(*low, __l)) break;
+        if (m & print && iswprint_l(*low, __l)) break;
+        if (m & cntrl && iswcntrl_l(*low, __l)) break;
+        if (m & upper && iswupper_l(*low, __l)) break;
+        if (m & lower && iswlower_l(*low, __l)) break;
+        if (m & alpha && iswalpha_l(*low, __l)) break;
+        if (m & digit && iswdigit_l(*low, __l)) break;
+        if (m & punct && iswpunct_l(*low, __l)) break;
+        if (m & xdigit && iswxdigit_l(*low, __l)) break;
+        if (m & blank && iswblank_l(*low, __l)) break;
 #endif
     }
     return low;