为什么C ++编译器在“ c：\\ program files \\ gnu emacs \\ include”中查找包含文件？

Question

I'm trying to compile curl from source (the zip file) in Windows 10 in order to get the curl library (which in turn is needed to build osgEarth ). However, when I have used CMake to generated the Visual Studio projects and I try to compile the ALL_BUILD project using the "default native compiler" (according to CMake), I'm getting a lot of errors, of which the first error says

c:\program files\gnu emacs\include\zconf.h(475): fatal error C1083: Cannot open include file: 'unistd.h': No such file or directory

Why does the compiler read c:\\program files\\gnu emacs\\include\\zconf.h ?

To me, it doesn't make any sense that it searches c:\\program files\\gnu emacs\\include for include files, since the compilation should be independent of whether emacs is installed (and if it hadn't been installed, this file wouldn't exist). I have searched through all environment variables to se if any of them could be telling the compiler to look in c:\\program files\\gnu emacs\\include for include files, but the only environment variables the term emacs exists in (case insensitive search) is PATH and ORIGINAL_PATH (which I don't know what it does).

Is it perhaps something in the CMake project that makes the compiler search this folder?

Answer 1

CMake tries to locate your local zlib install path. There are different possible locations, for more details check FindZLIB.cmake somehwere in your cmake install path. My local version will search in $ZLIB_ROOT or some windows registry key, maybe one of these variables have been set on your system when installing emacs.