我正在尝试使用 Rcpp 编写一些 C++ 代码来访问 Windows 中的一些操作系统级别的东西。一旦我包含windows.h
or shlobj.h
,我就会得到一堆编译错误。当我运行这段代码时,它可以工作,所以我知道我掌握了一些基础知识。但是,当我取消注释任何与 Windows 相关的行时#include
,它就不起作用了。
library(inline)
inc <- '
#include <iostream>
#include <stdio.h>
// #include <windows.h>
// #include <shlobj.h>
using namespace std;
'
src <- '
cout << "foo\\n";
printf("foo2\\n");
return Rcpp::wrap(20);
'
fun <- cxxfunction(signature(),
includes = inc,
src, plugin="Rcpp")
fun()
注意:当我在 RStudio 中运行它时,控制台的输出cout
和printf
出现在控制台中,但是当我从 Windows RGui 运行它时,输出不会出现。我认为这与 RGui 处理文本输出的方式有关。
当我取消注释这些包含行时,我得到的错误如下所示:
In file included from c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objbase.h:154:0,
from c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/ole2.h:16,
from c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/windows.h:94,
from file43c2f9e3518.cpp:22:
c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objidl.h:598:52: error: macro "Realloc" requires 3 arguments, but only 2 given
c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objidl.h:598:56: error: ISO C++ forbids initialization of member 'Realloc' [-fpermissive]
c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objidl.h:598:56: error: making 'Realloc' static [-fpermissive]
... 等等
关于如何使这项工作的任何提示?
更新:我设法消除了一些错误,但仍有一些错误。
Realloc
通过遵循http://tolstoy.newcastle.edu.au/R/e2/devel/06/11/1242.html的一些建议,我也得到了错误
inc
应替换为:
inc <- '
#include <iostream>
#include <stdio.h>
// This is taken from http://tolstoy.newcastle.edu.au/R/e2/devel/06/11/1242.html
#include <R.h>
#undef Realloc
#define R_Realloc(p,n,t) (t *) R_chk_realloc( (void *)(p), (size_t)((n) * sizeof(t)) )
#include <shlobj.h>
using namespace std;
'
我还通过传递-fpermissive
给编译器来消除其他错误,如来自这个问题:How to set g++ compiler flags using Rcpp and inline?
settings <- getPlugin("Rcpp")
settings$env$PKG_CXXFLAGS <- paste('-fpermissive',settings$env$PKG_CXXFLAGS,sep=' ')
fun <- cxxfunction(signature(), includes = inc,
src, plugin = "Rcpp",
settings = settings)
Sys.unsetenv('PKG_CXXFLAGS')
但是还是有一些错误:
In file included from c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objbase.h:154:0,
from c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/ole2.h:16,
from c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/shlobj.h:86,
from file43c267d3279.cpp:26:
c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objidl.h:599:25: error: expected identifier before '(' token
c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objidl.h:599:25: error: 'parameter' declared as function returning a function
c:\rtools\gcc-4.6.3\bin\../lib/gcc/i686-w64-mingw32/4.6.3/../../../../i686-w64-mingw32/include/objidl.h:599:25: error: expected ')' before ',' token