在 RefPerSys适用于 Linux/x86-64 的 GPLv3+ 项目 (在 Debian/Sid 系统上),git commit 37172c9af257865d , 编译 GCC 10 , 调用为 g++ -std=gnu++17 -Og -g3 -Wall -Wextra
等等...我收到以下错误消息:
refpersys.hh: In instantiation of ‘PaylClass* Rps_ObjectZone::put_new_arg3_payload(Arg1Class, Arg2Class, Arg3Class) [with PaylClass = Rps_PayloadWebex; Arg1Class = long unsigned int; Arg2Class = Onion::Request*; Arg3Class = Onion::Response*]’:
httpweb_rps.cc:314:71: required from here
refpersys.hh:2162:76: error: no matching function for call to ‘Rps_ObjectZone::rps_allocate4<Rps_PayloadWebex, long unsigned int, Onion::Request*, Onion::Response*>(Rps_ObjectZone*, long unsigned int&, Onion::Request*&, Onion::Response*&)’
2162 | Zone::rps_allocate4<PaylClass,Arg1Class,Arg2Class,Arg3Class>(this,arg1,arg2,arg3);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
In file included from headweb_rps.hh:37,
from httpweb_rps.cc:34:
refpersys.hh:1701:3: note: candidate: ‘template<class ZoneClass, class Arg1Class, class Arg2Class, class Arg3Class, class Arg4Class> static ZoneClass* Rps_QuasiZone::rps_allocate4(Arg1Class, Arg2Class, Arg3Class, Arg4Class)’
1701 | rps_allocate4(Arg1Class arg1, Arg2Class arg2, Arg3Class arg3, Arg4Class arg4)
| ^~~~~~~~~~~~~
refpersys.hh:1701:3: note: template argument deduction/substitution failed:
In file included from headweb_rps.hh:37,
from httpweb_rps.cc:34:
refpersys.hh:2162:76: note: cannot convert ‘(Rps_ObjectZone*)this’ (type ‘Rps_ObjectZone*’) to type ‘long unsigned int’
2162 | Zone::rps_allocate4<PaylClass,Arg1Class,Arg2Class,Arg3Class>(this,arg1,arg2,arg3);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
我不太容易举一个小例子,但我可以给出以下解释。它是关于使用多线程实现(和 Web 界面,使用我们的精确跟踪垃圾收集器)实现一些动态类型语言(如规则的专家系统,语义上受 Common Lisp 启发)。主要头文件是
refpersys.hh
并且是 #include
d 无处不在。伴随的头文件是 headweb_rps.hh
仅与使用 libonion 的 Web 相关代码相关,这是一些 HTTP 服务器库(具有命名空间 Onion::
),它是 #include
正在refpersys.hh
标题。在 C++ 意义上没有使用多重继承。
我们有一个枚举
Rps_Type
(在文件 refpersys.hh
第 903 行)定义一些 tagged union 的标签类型。标记的 union 类型是顶级 Rps_TypedZone
(在文件 refpersys.hh
第 1630 行)带有明显的构造函数 Rps_TypedZone::Rps_TypedZone(const Rps_Type ty)
定义于 refpersys.hh
第 1637 行。我们有一个
class Rps_QuasiZone
Rps_TypedZone
的子类(在文件 refpersys.hh
第 1646 行)。我们有一个
class Rps_ZoneValue
(在 refpersys.hh:1755
中)Rps_QuasiZone
的子类.class Rps_ObjectZone
(在 refpersys.hh:1964
中)是 Rps_ZoneValue
的子类.让我们将 RefPerSys 对象调用为该 Rps_ObjectZone
的子类的任何 C++ 实例。 .class Rps_ObjectRef
(在 refpersys.hh:694
中)是我们的 GC-ed 智能指针,指向 Rps_ObjectZone
.class Rps_Value
(在 refpersys.hh:967
中)是一个单字智能指针(有点像在 Common Lisp 中, SBCL -value 之类)。class Rps_Payload
(在 refpersys.hh:2264
中)在 Rps_ObjectZone
中携带一些可选的额外数据.每个这样的有效负载都属于一个 RefPerSys 对象(一些 Rps_ObjectZone
),称为其所有者。put_new_arg3_payload
Rps_ObjectZone
的模板成员函数很简单(在 refpersys.hh:2157
和以下几行中)与 ob_payload
是 Rps_ObjectZone
的成员字段声明为 std::atomic<Rps_Payload*> ob_payload;
在线refpersys.hh:1981
: PaylClass* put_new_arg3_payload(Arg1Class arg1, Arg2Class arg2, Arg3Class arg3)
{
std::lock_guard<std::recursive_mutex> gu(ob_mtx);
PaylClass*newpayl =
Rps_QuasiZone::rps_allocate4<PaylClass,Arg1Class,Arg2Class,Arg3Class>(this,arg1,arg2,arg3);
Rps_Payload*oldpayl = ob_payload.exchange(newpayl);
if (oldpayl)
delete oldpayl;
return newpayl;
}; // end put_new_arg3_payload
许多 Web 交互(即 HTTP 请求,在 C++ 中为 Onion::Request
,以及相应的 HTTP 回复,在 C++ 中为 Onion::Reply
,本身是 C++ std::ostream
的子类)被具体化为 class Rps_PayloadWebex
的 C++ 实例在文件中声明 headweb_rps.hh
第 65 行,以及 Rps_Payload
的子类.模板成员函数
Rps_QuasiZone::rps_allocate4
定义(在 refpersys.hh:1699
行)为:template <typename ZoneClass, typename Arg1Class, typename Arg2Class, typename Arg3Class, typename Arg4Class>
static ZoneClass*
rps_allocate4(Arg1Class arg1, Arg2Class arg2, Arg3Class arg3, Arg4Class arg4)
{
return new(nullptr) ZoneClass(arg1, arg2, arg3, arg4);
};
我们的“解释器”的调用帧被具体化为 class Rps_ProtoCallFrame;
我们有(在 refpersys.hh
第 691 行)一个 typedef Rps_ProtoCallFrame Rps_CallFrame;
class Rps_ProtoCallFrame
是 Rps_TypedZone
的子类定义于 refpersys.hh:2823
.故障线路
httpweb_rps.cc:314
在里面: Rps_ObjectRef
Rps_PayloadWebex::make_obwebex(Rps_CallFrame*callerframe, Onion::Request*req, Onion::Response*resp,
uint64_t reqnum)
{
RPS_ASSERT(callerframe != nullptr && callerframe->is_good_call_frame());
RPS_ASSERT(req != nullptr);
RPS_ASSERT(resp != nullptr);
auto web_exchange_ob = RPS_ROOT_OB(_8zNtuRpzXUP013WG9S);
RPS_DEBUG_LOG(WEB, "Rps_PayloadWebex::make_obwebex start reqnum#" << reqnum
);
RPS_LOCALFRAME(/*descr:*/ web_exchange_ob,
/*prev:*/callerframe,
/*locals:*/
Rps_ObjectRef obwebex);
_f.obwebex = Rps_ObjectRef::make_object(&_, web_exchange_ob);
auto paylwebex = ////////////////////////////////////// FAULTY LINE BELOW
_f.obwebex->put_new_arg3_payload<Rps_PayloadWebex>(reqnum,req,resp);
RPS_DEBUG_LOG(WEB, "Rps_PayloadWebex::make_obwebex end reqnum#" << reqnum
<< " obwebex=" << _f.obwebex << " startim:" << paylwebex->webex_startim);
RPS_ASSERT(paylwebex != nullptr);
return _f.obwebex;
} // end PayloadWebex::make_obwebex
在上面的代码中,RPS_ASSERT
, RPS_ROOT_OB
, RPS_LOCALFRAME
, RPS_DEBUG_LOG
是 C++ 宏。上述代码的宏展开为:Rps_ObjectRef
Rps_PayloadWebex::make_obwebex(Rps_CallFrame*callerframe, Onion::Request*req, Onion::Response*resp,
uint64_t reqnum)
{
do { if (__builtin_expect(!!(!((callerframe != nullptr
&& callerframe->is_good_call_frame()))),0))
{ fprintf(
//# 302 "httpweb_rps.cc" 3
stderr
//# 302 "httpweb_rps.cc"
, "\n\n" "%s*** RefPerSys ASSERT failed: %s%s\n" "%s:%d: {%s}\n\n", (rps_stderr_istty?(rps_without_terminal_escape?"":"\033[1m"):""),
"(callerframe != nullptr && callerframe->is_good_call_frame())",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[0m"):""),
"httpweb_rps.cc",302,__PRETTY_FUNCTION__);
rps_fatal_stop_at("httpweb_rps.cc",302); }}
while(0);
do
{ if (__builtin_expect(!!(!((req != nullptr))),0)) {
fprintf(
//# 303 "httpweb_rps.cc" 3
stderr
//# 303 "httpweb_rps.cc"
, "\n\n" "%s*** RefPerSys ASSERT failed: %s%s\n" "%s:%d: {%s}\n\n",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[1m"):""), "(req != nullptr)",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[0m"):""), "httpweb_rps.cc",303,__PRETTY_FUNCTION__);
rps_fatal_stop_at("httpweb_rps.cc",303); }} while(0);
do { if (__builtin_expect(!!(!((resp != nullptr))),0)) {
fprintf(
//# 304 "httpweb_rps.cc" 3
stderr
//# 304 "httpweb_rps.cc"
, "\n\n" "%s*** RefPerSys ASSERT failed: %s%s\n" "%s:%d: {%s}\n\n",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[1m"):""), "(resp != nullptr)",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[0m"):""), "httpweb_rps.cc",304,__PRETTY_FUNCTION__);
rps_fatal_stop_at("httpweb_rps.cc",304); }} while(0);
auto web_exchange_ob = rps_rootob_8zNtuRpzXUP013WG9S;
do { if ((rps_debug_flags & (1 << RPS_DEBUG_WEB)))
{ std::ostringstream _logstream_306;
_logstream_306 << "Rps_PayloadWebex::make_obwebex start reqnum#" << reqnum << std::flush;
rps_debug_printf_at("httpweb_rps.cc", 306, RPS_DEBUG_WEB,
"%s", _logstream_306.str().c_str()); } } while (0)
;
struct RpsFrameData308 {/*locals:*/ Rps_ObjectRef obwebex; };
typedef Rps_FieldedCallFrame<RpsFrameData308> Rps_FldCallFrame308;
class Rps_FrameAt308 : public Rps_FldCallFrame308
{ public:
Rps_FrameAt308(Rps_ObjectRef obd308, Rps_CallFrame* prev308) :
Rps_FldCallFrame308(obd308, prev308) { }; };
Rps_FrameAt308 _((/*descr:*/ web_exchange_ob),(/*prev:*/callerframe));
auto& _f = *_.fieldsptr();
;
_f.obwebex = Rps_ObjectRef::make_object(&_, web_exchange_ob);
auto paylwebex =
_f.obwebex->put_new_arg3_payload<Rps_PayloadWebex>(reqnum,req,resp);
do { if ((rps_debug_flags & (1 << RPS_DEBUG_WEB)))
{ std::ostringstream _logstream_315;
_logstream_315 << "Rps_PayloadWebex::make_obwebex end reqnum#"
<< reqnum << " obwebex=" << _f.obwebex << " startim:"
<< paylwebex->webex_startim << std::flush; rps_debug_printf_at("httpweb_rps.cc",
315, RPS_DEBUG_WEB, "%s",
_logstream_315.str().c_str()); } } while (0)
;
do { if (__builtin_expect(!!(!((paylwebex != nullptr))),0)) {
fprintf(
//# 317 "httpweb_rps.cc" 3
stderr
//# 317 "httpweb_rps.cc"
, "\n\n" "%s*** RefPerSys ASSERT failed: %s%s\n" "%s:%d: {%s}\n\n",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[1m"):""), "(paylwebex != nullptr)",
(rps_stderr_istty?(rps_without_terminal_escape?"":"\033[0m"):""), "httpweb_rps.cc",317,__PRETTY_FUNCTION__);
rps_fatal_stop_at("httpweb_rps.cc",317); }} while(0);
return _f.obwebex;
} // end PayloadWebex::make_obwebex
我究竟做错了什么?
最佳答案
错误消息末尾的这一行很清楚,它暗示 long unsigned int
应该找...
cannot convert ‘(Rps_ObjectZone*)this’ (type ‘Rps_ObjectZone*’) to type ‘long unsigned int’
这与错误消息开头的这一行有关:refpersys.hh:2162:76: error: no matching function for call to Rps_ObjectZone::rps_allocate4<Rps_PayloadWebex, long unsigned int, Onion::Request*, Onion::Response*>(Rps_ObjectZone*, long unsigned int&, Onion::Request*&, Onion::Response*&)’
这是第一行错误:refpersys.hh: In instantiation of ‘PaylClass* Rps_ObjectZone::put_new_arg3_payload(Arg1Class, Arg2Class, Arg3Class) [with PaylClass = Rps_PayloadWebex; Arg1Class = long unsigned int; Arg2Class = Onion::Request*; Arg3Class = Onion::Response*
重要的部分是Arg1Class = long unsigned int;
这一切意味着long unsigned int
(变量 reqnum
的类型不是您调用中的第一个参数的有效类型_f.obwebex->put_new_arg3_payload<Rps_PayloadWebex>();
似乎 ArgClass1 至少应该是某种指针,更有可能是指向从 Rps_ObjectZone
派生的类型的指针。 .我没有使用过这个特定的库,但这就是错误消息的意思。
我认为最可能的错误是您混淆了此函数调用的前两个参数的顺序。
Rps_QuasiZone::rps_allocate4<PaylClass,Arg1Class,Arg2Class,Arg3Class> (this,arg1,arg2,arg3);
要么在那里,要么在对类 ZoneClass
的构造函数的调用中.参数的混合顺序只是一个假设,我没有看到你的类
ZoneClass
的构造函数.作为旁注:如果
Arg1Class
必须可转换为 ZoneClass*
,这意味着有问题的代码在不应该声明的地方声明了模板参数类型。
关于c++ - 为什么 C++ 模板实例化失败?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/64692976/