Add some tests to ensure that the __regex_word does not conflict with any of ctype_base's values.

Hopefully this will catch cases like https://llvm.org/bugs/show_bug.cgi?id=26476 in the future.

llvm-svn: 260527

1 files changed, 13 insertions, 0 deletions

diff --git a/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp b/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp
index 0b1b18eb507..d3e5a5caa21 100644
--- a/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp
+++ b/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp
@@ -33,6 +33,19 @@ test(const char_type* A,
 
 int main()
 {
+//  if __regex_word is not distinct from all the classes, bad things happen
+//  See https://llvm.org/bugs/show_bug.cgi?id=26476 for an example.
+    assert((std::ctype_base::space  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::print  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::cntrl  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::upper  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::lower  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::alpha  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::digit  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::punct  & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::xdigit & std::regex_traits<char>::__regex_word) == 0);
+    assert((std::ctype_base::blank  & std::regex_traits<char>::__regex_word) == 0);
+
     test("d", std::ctype_base::digit);
     test("D", std::ctype_base::digit);
     test("d", std::ctype_base::digit, true);