[PATCH 9/9]: C++ P0482R5 char8_t: Updates to gdb pretty printing support

[Tom Honermann]

This patch adds recognition of the u8string and u8string_view type 
aliases to the gdb pretty printer extension.

libstdc++-v3/ChangeLog:
2018-11-04  Tom Honermann  <t...@honermann.net>

     * python/libstdcxx/v6/printers.py (register_type_printers): Add
     type printers for u8string and u8string_view.
     * testsuite/libstdc++-prettyprinters/whatis.cc: Validate
     recognition of u8string.

Tom.
diff --git a/libstdc++-v3/python/libstdcxx/v6/printers.py b/libstdc++-v3/python/libstdcxx/v6/printers.py
index 827c87b70ea..f9e638e210d 100644
--- a/libstdc++-v3/python/libstdcxx/v6/printers.py
+++ b/libstdc++-v3/python/libstdcxx/v6/printers.py
@@ -1554,7 +1554,7 @@ def register_type_printers(obj):
         return
 
     # Add type printers for typedefs std::string, std::wstring etc.
-    for ch in ('', 'w', 'u16', 'u32'):
+    for ch in ('', 'w', 'u8', 'u16', 'u32'):
         add_one_type_printer(obj, 'basic_string', ch + 'string')
         add_one_type_printer(obj, '__cxx11::basic_string', ch + 'string')
         # Typedefs for __cxx11::basic_string used to be in namespace __cxx11:
@@ -1604,7 +1604,7 @@ def register_type_printers(obj):
 
     # Add type printers for experimental::basic_string_view typedefs.
     ns = 'experimental::fundamentals_v1::'
-    for ch in ('', 'w', 'u16', 'u32'):
+    for ch in ('', 'w', 'u8', 'u16', 'u32'):
         add_one_type_printer(obj, ns + 'basic_string_view',
                              ns + ch + 'string_view')
 
diff --git a/libstdc++-v3/testsuite/libstdc++-prettyprinters/whatis.cc b/libstdc++-v3/testsuite/libstdc++-prettyprinters/whatis.cc
index 90f3994314b..d74bf7c5e9b 100644
--- a/libstdc++-v3/testsuite/libstdc++-prettyprinters/whatis.cc
+++ b/libstdc++-v3/testsuite/libstdc++-prettyprinters/whatis.cc
@@ -1,5 +1,5 @@
 // { dg-do run { target c++11 } }
-// { dg-options "-g -O0" }
+// { dg-options "-g -O0 -fchar8_t" }
 // { dg-skip-if "" { *-*-* } { "-D_GLIBCXX_PROFILE" } }
 
 // Copyright (C) 2011-2018 Free Software Foundation, Inc.
@@ -130,6 +130,9 @@ holder<std::cregex_token_iterator> cregex_token_iterator_holder;
 std::sregex_token_iterator *sregex_token_iterator_ptr;
 holder<std::sregex_token_iterator> sregex_token_iterator_holder;
 // { dg-final { whatis-test sregex_token_iterator_holder "holder<std::sregex_token_iterator>" } }
+std::u8string *u8string_ptr;
+holder<std::u8string> u8string_holder;
+// { dg-final { whatis-test u8string_holder "holder<std::u8string>" } }
 std::u16string *u16string_ptr;
 holder<std::u16string> u16string_holder;
 // { dg-final { whatis-test u16string_holder "holder<std::u16string>" } }
@@ -240,6 +243,8 @@ main()
   placeholder(&cregex_token_iterator_holder);
   placeholder(&sregex_token_iterator_ptr);
   placeholder(&sregex_token_iterator_holder);
+  placeholder(&u8string_ptr);
+  placeholder(&u8string_holder);
   placeholder(&u16string_ptr);
   placeholder(&u16string_holder);
   placeholder(&u32string_ptr);