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-rw-r--r--build-aux/snippet/c++defs.h89
1 files changed, 67 insertions, 22 deletions
diff --git a/build-aux/snippet/c++defs.h b/build-aux/snippet/c++defs.h
index 585b38ab..2b819da5 100644
--- a/build-aux/snippet/c++defs.h
+++ b/build-aux/snippet/c++defs.h
@@ -1,5 +1,5 @@
/* C++ compatible function declaration macros.
- Copyright (C) 2010-2015 Free Software Foundation, Inc.
+ Copyright (C) 2010-2016 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published
@@ -17,6 +17,15 @@
#ifndef _GL_CXXDEFS_H
#define _GL_CXXDEFS_H
+/* Begin/end the GNULIB_NAMESPACE namespace. */
+#if defined __cplusplus && defined GNULIB_NAMESPACE
+# define _GL_BEGIN_NAMESPACE namespace GNULIB_NAMESPACE {
+# define _GL_END_NAMESPACE }
+#else
+# define _GL_BEGIN_NAMESPACE
+# define _GL_END_NAMESPACE
+#endif
+
/* The three most frequent use cases of these macros are:
* For providing a substitute for a function that is missing on some
@@ -111,14 +120,25 @@
that redirects to rpl_func, if GNULIB_NAMESPACE is defined.
Example:
_GL_CXXALIAS_RPL (open, int, (const char *filename, int flags, ...));
- */
+
+ Wrapping rpl_func in an object with an inline conversion operator
+ avoids a reference to rpl_func unless GNULIB_NAMESPACE::func is
+ actually used in the program. */
#define _GL_CXXALIAS_RPL(func,rettype,parameters) \
_GL_CXXALIAS_RPL_1 (func, rpl_##func, rettype, parameters)
#if defined __cplusplus && defined GNULIB_NAMESPACE
# define _GL_CXXALIAS_RPL_1(func,rpl_func,rettype,parameters) \
namespace GNULIB_NAMESPACE \
{ \
- rettype (*const func) parameters = ::rpl_func; \
+ static const struct _gl_ ## func ## _wrapper \
+ { \
+ typedef rettype (*type) parameters; \
+ \
+ inline operator type () const \
+ { \
+ return ::rpl_func; \
+ } \
+ } func = {}; \
} \
_GL_EXTERN_C int _gl_cxxalias_dummy
#else
@@ -135,8 +155,15 @@
# define _GL_CXXALIAS_RPL_CAST_1(func,rpl_func,rettype,parameters) \
namespace GNULIB_NAMESPACE \
{ \
- rettype (*const func) parameters = \
- reinterpret_cast<rettype(*)parameters>(::rpl_func); \
+ static const struct _gl_ ## func ## _wrapper \
+ { \
+ typedef rettype (*type) parameters; \
+ \
+ inline operator type () const \
+ { \
+ return reinterpret_cast<type>(::rpl_func); \
+ } \
+ } func = {}; \
} \
_GL_EXTERN_C int _gl_cxxalias_dummy
#else
@@ -150,19 +177,24 @@
is defined.
Example:
_GL_CXXALIAS_SYS (open, int, (const char *filename, int flags, ...));
- */
+
+ Wrapping func in an object with an inline conversion operator
+ avoids a reference to func unless GNULIB_NAMESPACE::func is
+ actually used in the program. */
#if defined __cplusplus && defined GNULIB_NAMESPACE
- /* If we were to write
- rettype (*const func) parameters = ::func;
- like above in _GL_CXXALIAS_RPL_1, the compiler could optimize calls
- better (remove an indirection through a 'static' pointer variable),
- but then the _GL_CXXALIASWARN macro below would cause a warning not only
- for uses of ::func but also for uses of GNULIB_NAMESPACE::func. */
-# define _GL_CXXALIAS_SYS(func,rettype,parameters) \
- namespace GNULIB_NAMESPACE \
- { \
- static rettype (*func) parameters = ::func; \
- } \
+# define _GL_CXXALIAS_SYS(func,rettype,parameters) \
+ namespace GNULIB_NAMESPACE \
+ { \
+ static const struct _gl_ ## func ## _wrapper \
+ { \
+ typedef rettype (*type) parameters; \
+ \
+ inline operator type () const \
+ { \
+ return ::func; \
+ } \
+ } func = {}; \
+ } \
_GL_EXTERN_C int _gl_cxxalias_dummy
#else
# define _GL_CXXALIAS_SYS(func,rettype,parameters) \
@@ -178,8 +210,15 @@
# define _GL_CXXALIAS_SYS_CAST(func,rettype,parameters) \
namespace GNULIB_NAMESPACE \
{ \
- static rettype (*func) parameters = \
- reinterpret_cast<rettype(*)parameters>(::func); \
+ static const struct _gl_ ## func ## _wrapper \
+ { \
+ typedef rettype (*type) parameters; \
+ \
+ inline operator type () const \
+ { \
+ return reinterpret_cast<type>(::func); \
+ } \
+ } func = {}; \
} \
_GL_EXTERN_C int _gl_cxxalias_dummy
#else
@@ -202,9 +241,15 @@
# define _GL_CXXALIAS_SYS_CAST2(func,rettype,parameters,rettype2,parameters2) \
namespace GNULIB_NAMESPACE \
{ \
- static rettype (*func) parameters = \
- reinterpret_cast<rettype(*)parameters>( \
- (rettype2(*)parameters2)(::func)); \
+ static const struct _gl_ ## func ## _wrapper \
+ { \
+ typedef rettype (*type) parameters; \
+ \
+ inline operator type () const \
+ { \
+ return reinterpret_cast<type>((rettype2 (*) parameters2)(::func)); \
+ } \
+ } func = {}; \
} \
_GL_EXTERN_C int _gl_cxxalias_dummy
#else