Linux: change to posix style

[DimStar77]

replace it by defined(linux)

[JonathonReinhart]

Care to elaborate on this change? Under what circumstances is __linux__ defined as opposed to linux?

[DimStar77]

Sure.. nothing easier than that.

Take this very dummy c++ 'code':

#if defined(linux)
  #warning linux is defined
#endif
#if defined(__linux__)
  #warning __linux__ is defined
#endif

int main() {
  return 0;
}

then compile it twice, once using:

g++ test.cpp

test.cpp:4:4: warning: #warning linux is defined [-Wcpp]
#warning linux is defined
^
test.cpp:7:4: warning: #warning linux is defined [-Wcpp]
#warning linux is defined

And once using

g++ test.cpp -std=c++11
test.cpp:7:4: warning: #warning linux is defined [-Wcpp]
#warning linux is defined
^

Building using c++11 standard does NOT provide the linux defines...
and c++11 is mandatory nowadays when building against recent stack of libsigc++ / libglibmm

[JonathonReinhart]

Thanks @DimStar77. This was mainly for my own curiosity, but it may help get this PR merged, too. That is, if anyone from @vmware pays any attention to it.

[vmwclabot]

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[vmwclabot]

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[bzed]

In the meantime compiling with -std=gnu++11 works well :)

[mikini]

Confusing read! For anyone also puzzled by the thread above and maybe not looking at the patch, notice the text emphasized in bold and surround those with __. In the markdown formatting used here double underscore, as in the standard compiler defines, are translated into bold text unless marked otherwise.

Original PR text 'code' quoted:
replace it by defined(__linux__)

And the gcc output (my execution):

$ g++ test.cpp 
test.cpp:2:4: warning: #warning linux is defined [-Wcpp]
   #warning linux is defined
    ^
test.cpp:5:4: warning: #warning __linux__ is defined [-Wcpp]
   #warning __linux__ is defined
    ^
$ g++ test.cpp -std=c++11
test.cpp:5:4: warning: #warning __linux__ is defined [-Wcpp]
   #warning __linux__ is defined
    ^

Still unmerged though. Things busy at VMware?

[stanguturi]

Thanks. We have created an internal bug to track it.