[libdazzle] build: fix compilation with c++

[Christian Hergert <chergert src gnome org>]

commit e2efb169d96c1e8ef6fa67762572d715d52d9e57
Author: Christian Hergert <chergert redhat com>
Date:   Sat May 30 17:23:21 2020 -0700

    build: fix compilation with c++
    
    Fixes #54

 src/util/dzl-int-pair.h | 4 ++--
 src/util/dzl-macros.h   | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/src/util/dzl-int-pair.h b/src/util/dzl-int-pair.h
index b66992b..887aa73 100644
--- a/src/util/dzl-int-pair.h
+++ b/src/util/dzl-int-pair.h
@@ -87,7 +87,7 @@ dzl_int_pair_new (gint first, gint second)
   pair.second = second;
 
 #ifdef DZL_INT_PAIR_64
-  return pair.ptr;
+  return (DzlIntPair *)pair.ptr;
 #else
   return g_slice_copy (sizeof (DzlIntPair), &pair);
 #endif
@@ -110,7 +110,7 @@ dzl_uint_pair_new (guint first, guint second)
   pair.second = second;
 
 #ifdef DZL_INT_PAIR_64
-  return pair.ptr;
+  return (DzlUIntPair *)pair.ptr;
 #else
   return g_slice_copy (sizeof (DzlUIntPair), &pair);
 #endif
diff --git a/src/util/dzl-macros.h b/src/util/dzl-macros.h
index bb36c1c..09332a0 100644
--- a/src/util/dzl-macros.h
+++ b/src/util/dzl-macros.h
@@ -94,7 +94,7 @@ dzl_str_equal0 (gconstpointer str1,
 {
   /* We use gconstpointer so that we can allow
    * both signed and unsigned chars here (such as xmlChar). */
-  return g_strcmp0 (str1, str2) == 0;
+  return g_strcmp0 ((const gchar *)str1, (const gchar *)str2) == 0;
 }
 
 static inline void