4 files changed, 23 insertions, 7 deletions
diff --git a/src/libgamma-error.hh b/src/libgamma-error.hh
index 12550f2..0bd0fce 100644
--- a/src/libgamma-error.hh
+++ b/src/libgamma-error.hh
@@ -25,6 +25,10 @@
 #include "libgamma-native.hh"
 
 
+#ifndef __GCC__
+# define __attribute__(X) /* emtpy */
+#endif
+
 
 #ifndef __WIN32__
 # define libgamma_gid_t  gid_t
@@ -82,7 +86,7 @@ namespace libgamma
    * @return        The error code, zero if the name is `nullptr`
    *                or does not refer to a `libgamma` error.
    */
-  int value_of_error(const std::string* name);
+  int value_of_error(const std::string* name) __attribute__((pure));
   
   
   /**
@@ -122,9 +126,9 @@ namespace libgamma
       return *this;
     }
     
-    operator char*() const
+    operator const char*() const
     {
-      return (char*)libgamma_group_name;
+      return libgamma_group_name;
     }
   };
   
diff --git a/src/libgamma-facade.hh b/src/libgamma-facade.hh
index c52d7d8..c08521a 100644
--- a/src/libgamma-facade.hh
+++ b/src/libgamma-facade.hh
@@ -26,6 +26,12 @@
 #include "libgamma-method.hh"
 
 
+#ifndef __GCC__
+# define __attribute__(X) /* emtpy */
+#endif
+
+
+
 namespace libgamma
 {
   /**
@@ -49,7 +55,7 @@ namespace libgamma
    * @param   method  The adjustment method.
    * @return          Whether the adjustment method is available.
    */
-  int is_method_available(int method);
+  int is_method_available(int method) __attribute__((const));
   
   /**
    * Return the capabilities of an adjustment method.
diff --git a/src/libgamma-method.cc b/src/libgamma-method.cc
index 18bb9bb..16d61ff 100644
--- a/src/libgamma-method.cc
+++ b/src/libgamma-method.cc
@@ -202,13 +202,13 @@ namespace libgamma
     gamma_depth_error(info->gamma_depth_error),
     gamma_support(info->gamma_support),
     gamma_support_error(info->gamma_support_error),
-    subpixel_order((SubpixelOrder)(info->subpixel_order)),
+    subpixel_order(info->subpixel_order),
     subpixel_order_error(info->subpixel_order_error),
     active(info->active),
     active_error(info->active_error),
     connector_name(nullptr),
     connector_name_error(info->connector_name_error),
-    connector_type((ConnectorType)(info->connector_type)),
+    connector_type(info->connector_type),
     connector_type_error(info->connector_type_error),
     gamma_red(info->gamma_red),
     gamma_green(info->gamma_green),
diff --git a/src/libgamma-method.hh b/src/libgamma-method.hh
index aedf6f6..d4bfed3 100644
--- a/src/libgamma-method.hh
+++ b/src/libgamma-method.hh
@@ -26,6 +26,12 @@
 #include "libgamma-error.hh"
 
 
+#ifndef __GCC__
+# define __attribute__(X) /* emtpy */
+#endif
+
+
+
 namespace libgamma
 {
   /**
@@ -102,7 +108,7 @@ namespace libgamma
     /**
      * Destructor.
      */
-    ~MethodCapabilities();
+    ~MethodCapabilities() __attribute__((const));
     
     /**
      * Copy operator.