我正在尝试使用Intels HLS编译器编译一个简单的乘数示例，并继续获取实例化未声明标识符的错误。使用
export CPLUS_INCLUDE_PATH=$CPLUS_INCLUDE_PATH:/usr/include/x86_64-linux-gnu/c++/7
在makefile中包含以下路径已删除了与查找c ++ config.h相关的所有错误，但下面的两个仍然存在：
i++ -march=x86-64 mult.cpp -o emu.exe
In file included from mult.cpp:1:
In file included from /home/themajesticbaker/intelFPGA_lite/17.1/hls/include/HLS/hls.h:11:
In file included from /home/themajesticbaker/intelFPGA_lite/17.1/hls/include/HLS/hls_internal.h:10:
In file included from /usr/lib/gcc/x86_64-linux-gnu/7.2.0/../../../../include/c++/7.2.0/stdlib.h:36:
In file included from /usr/lib/gcc/x86_64-linux-gnu/7.2.0/../../../../include/c++/7.2.0/cstdlib:76:
/usr/lib/gcc/x86_64-linux-gnu/7.2.0/../../../../include/c++/7.2.0/bits/std_abs.h:55:26: error: use of undeclared identifier
'__builtin_labs'
abs(long __i) { return __builtin_labs(__i); }
^
/usr/lib/gcc/x86_64-linux-gnu/7.2.0/../../../../include/c++/7.2.0/bits/std_abs.h:60:31: error: use of undeclared identifier
'__builtin_llabs'
abs(long long __x) { return __builtin_llabs (__x); }
^
2 errors generated.
HLS x86-64 compile FAILED.
std_abs.h文件似乎有问题。有趣的是，发现/ usr -name std_abs.h只返回了一个位置：/usr/include/c++/7/bits/std_abs.h-这里是源代码：
// -*- C++ -*- C library enhancements header.
// Copyright (C) 2016-2017 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file include/bits/std_abs.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{cmath, cstdlib}
*/
#ifndef _GLIBCXX_BITS_STD_ABS_H
#define _GLIBCXX_BITS_STD_ABS_H
#pragma GCC system_header
#include <bits/c++config.h>
#define _GLIBCXX_INCLUDE_NEXT_C_HEADERS
#include_next <stdlib.h>
#ifdef __CORRECT_ISO_CPP_MATH_H_PROTO
# include_next <math.h>
#endif
#undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS
#undef abs
extern "C++"
{
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
using ::abs;
#ifndef __CORRECT_ISO_CPP_STDLIB_H_PROTO
inline long
abs(long __i) { return __builtin_labs(__i); }
#endif
#ifdef _GLIBCXX_USE_LONG_LONG
inline long long
abs(long long __x) { return __builtin_llabs (__x); }
#endif
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2192. Validity and return type of std::abs(0u) is unclear
// 2294. <cstdlib> should declare abs(double)
#ifndef __CORRECT_ISO_CPP_MATH_H_PROTO
inline _GLIBCXX_CONSTEXPR double
abs(double __x)
{ return __builtin_fabs(__x); }
inline _GLIBCXX_CONSTEXPR float
abs(float __x)
{ return __builtin_fabsf(__x); }
inline _GLIBCXX_CONSTEXPR long double
abs(long double __x)
{ return __builtin_fabsl(__x); }
#endif
#if defined(__GLIBCXX_TYPE_INT_N_0)
inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_0
abs(__GLIBCXX_TYPE_INT_N_0 __x) { return __x >= 0 ? __x : -__x; }
#endif
#if defined(__GLIBCXX_TYPE_INT_N_1)
inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_1
abs(__GLIBCXX_TYPE_INT_N_1 __x) { return __x >= 0 ? __x : -__x; }
#endif
#if defined(__GLIBCXX_TYPE_INT_N_2)
inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_2
abs(__GLIBCXX_TYPE_INT_N_2 __x) { return __x >= 0 ? __x : -__x; }
#endif
#if defined(__GLIBCXX_TYPE_INT_N_3)
inline _GLIBCXX_CONSTEXPR __GLIBCXX_TYPE_INT_N_3
abs(__GLIBCXX_TYPE_INT_N_3 __x) { return __x >= 0 ? __x : -__x; }
#endif
#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128) && !defined(__CUDACC__)
inline _GLIBCXX_CONSTEXPR
__float128
abs(__float128 __x)
{ return __x < 0 ? -__x : __x; }
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
}
#endif // _GLIBCXX_BITS_STD_ABS_H
非常感谢任何帮助。