[gcc r9-9384] Have std::vector printer's iterator return bool for vector<bool>

[gcc r9-9384] Have std::vector printer's iterator return bool for vector<bool>

[Jonathan Wakely]

https://gcc.gnu.org/g:6cc765a7917004478770f27bade1ecbb55906ae0

commit r9-9384-g6cc765a7917004478770f27bade1ecbb55906ae0
Author: Michael Weghorn <m.weghorn@posteo.de>
Date:   Wed Jun 19 22:57:06 2019 +0000

    Have std::vector printer's iterator return bool for vector<bool>
    
    Have the pretty-printer for 'std::vector<bool>' return a
    value of type 'bool' rather than an 'int'.
    
    This way, the type is clear and that can be used for better
    display and a 'gdb.Value' constructed from the returned value
    will have type 'bool' again, not e.g. 'long long' as happened
    previously (at least with GDB 8.2.1 on amd64).
    
    2019-06-19  Michael Weghorn  <m.weghorn@posteo.de>
                Jonathan Wakely  <jwakely@redhat.com>
    
            PR libstdc++/90945
            * python/libstdcxx/v6/printers.py (StdVectorPrinter._iterator): Use
            values of type bool for vector<bool> elements.
            * testsuite/libstdc++-prettyprinters/simple.cc: Test vector<bool>.
            * testsuite/libstdc++-prettyprinters/simple11.cc: Likewise.
    
    Co-Authored-By: Jonathan Wakely <jwakely@redhat.com>
    
    (cherry picked from commit 36d0dada6773d7fd7c5ace64c90e723930a3b81e)

Diff:
---
 libstdc++-v3/python/libstdcxx/v6/printers.py                | 12 +++++-------
 libstdc++-v3/testsuite/libstdc++-prettyprinters/simple.cc   | 10 ++++++++++
 libstdc++-v3/testsuite/libstdc++-prettyprinters/simple11.cc | 10 ++++++++++
 3 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/libstdc++-v3/python/libstdcxx/v6/printers.py b/libstdc++-v3/python/libstdcxx/v6/printers.py
index 3082b0e4d8c..32b8210414a 100644
--- a/libstdc++-v3/python/libstdcxx/v6/printers.py
+++ b/libstdc++-v3/python/libstdcxx/v6/printers.py
@@ -422,16 +422,12 @@ class StdVectorPrinter:
             if self.bitvec:
                 if self.item == self.finish and self.so >= self.fo:
                     raise StopIteration
-                elt = self.item.dereference()
-                if elt & (1 << self.so):
-                    obit = 1
-                else:
-                    obit = 0
+                elt = bool(self.item.dereference() & (1 << self.so))
                 self.so = self.so + 1
                 if self.so >= self.isize:
                     self.item = self.item + 1
                     self.so = 0
-                return ('[%d]' % count, obit)
+                return ('[%d]' % count, elt)
             else:
                 if self.item == self.finish:
                     raise StopIteration
@@ -442,7 +438,7 @@ class StdVectorPrinter:
     def __init__(self, typename, val):
         self.typename = strip_versioned_namespace(typename)
         self.val = val
-        self.is_bool = val.type.template_argument(0).code  == gdb.TYPE_CODE_BOOL
+        self.is_bool = val.type.template_argument(0).code == gdb.TYPE_CODE_BOOL
 
     def children(self):
         return self._iterator(self.val['_M_impl']['_M_start'],
@@ -482,6 +478,8 @@ class StdVectorIteratorPrinter:
             return 'non-dereferenceable iterator for std::vector'
         return str(self.val['_M_current'].dereference())
 
+# TODO add printer for vector<bool>'s _Bit_iterator and _Bit_const_iterator
+
 class StdTuplePrinter:
     "Print a std::tuple"
 
diff --git a/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple.cc b/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple.cc
index 5b70e2b3159..86b7c27d861 100644
--- a/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple.cc
+++ b/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple.cc
@@ -117,6 +117,16 @@ main()
   std::vector<int>::iterator viter0;
 // { dg-final { note-test viter0 {non-dereferenceable iterator for std::vector} } }
 
+  std::vector<bool> vb;
+  vb.reserve(100);
+  vb.push_back(true);
+  vb.push_back(true);
+  vb.push_back(false);
+  vb.push_back(false);
+  vb.push_back(true);
+  vb.erase(vb.begin());
+// { dg-final { regexp-test vb {std::(__debug::)?vector<bool> of length 4, capacity 128 = \\{true, false, false, true\\}} } }
+
   __gnu_cxx::slist<int> sll;
   sll.push_front(23);
   sll.push_front(47);
diff --git a/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple11.cc b/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple11.cc
index d24af91d0ea..5d47bdcd648 100644
--- a/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple11.cc
+++ b/libstdc++-v3/testsuite/libstdc++-prettyprinters/simple11.cc
@@ -110,6 +110,16 @@ main()
   std::vector<int>::iterator viter0;
 // { dg-final { note-test viter0 {non-dereferenceable iterator for std::vector} } }
 
+  std::vector<bool> vb;
+  vb.reserve(100);
+  vb.push_back(true);
+  vb.push_back(true);
+  vb.push_back(false);
+  vb.push_back(false);
+  vb.push_back(true);
+  vb.erase(vb.begin());
+// { dg-final { regexp-test vb {std::(__debug::)?vector<bool> of length 4, capacity 128 = \\{true, false, false, true\\}} } }
+
   __gnu_cxx::slist<int> sll;
   sll.push_front(23);
   sll.push_front(47);