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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">You can add PARENT_SCOPE to set command to set the value on the calling code.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Dvir<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> CMake [mailto:cmake-bounces@cmake.org]
<b>On Behalf Of </b>J Decker<br>
<b>Sent:</b> Tuesday, January 30, 2018 18:07<br>
<b>To:</b> Petr Kmoch <petr.kmoch@gmail.com><br>
<b>Cc:</b> CMake Mail List <cmake@cmake.org><br>
<b>Subject:</b> [Digital Signature Failure] Re: [CMake] Hard to do if in Macro<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Okay... but then with function I can't set external variables; but if( __ANDROID__ ) works.<o:p></o:p></p>
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<div>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">`result` never changes.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">---------------------------<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">set( __ANDROID__ 1 )<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">function( test __ANDROID__ RETVAL )<o:p></o:p></p>
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<div>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> if( ${__ANDROID__} EQUAL 1 OR ${__ANDROID__} STREQUAL "ON")<o:p></o:p></p>
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<div>
<p class="MsoNormal" style="background:white"><span style="font-family:"Arial",sans-serif;color:#222222"> set( ${RETVAL} ${${RETVAL}} qwer2 )<o:p></o:p></span></p>
</div>
</div>
<div>
<p class="MsoNormal"> message( "Included..... " )<o:p></o:p></p>
</div>
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<p class="MsoNormal"> endif( ${__ANDROID__} EQUAL 1 OR ${__ANDROID__} STREQUAL "ON")<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> if( __ANDROID__ )<o:p></o:p></p>
</div>
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<p class="MsoNormal"> set( ${RETVAL} ${${RETVAL}} asdf )<o:p></o:p></p>
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<p class="MsoNormal"> message( "ALWAYS Included ${__ANDROID__}" )<o:p></o:p></p>
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<p class="MsoNormal"> endif( __ANDROID__ )<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">endfunction( test ) <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">set( result "default" )<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<div>
<p class="MsoNormal">test( __ANDROID__ "result" )<o:p></o:p></p>
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<div>
<p class="MsoNormal">message( "REsult:${result}" )<o:p></o:p></p>
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<div>
<p class="MsoNormal"><o:p> </o:p></p>
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<div>
<p class="MsoNormal">test( ${__ANDROID__} "result" )<o:p></o:p></p>
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<div>
<p class="MsoNormal">message( "REsult:${result}" )<o:p></o:p></p>
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<div>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">test( OFF "result")<o:p></o:p></p>
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<p class="MsoNormal">message( "REsult:${result}" )<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">---------------------------<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222"><o:p> </o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Tue, Jan 30, 2018 at 12:35 AM, Petr Kmoch <<a href="mailto:petr.kmoch@gmail.com" target="_blank">petr.kmoch@gmail.com</a>> wrote:<o:p></o:p></p>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm">
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<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">Macros aren't functions, and macro parameters aren't CMake variables. Expanding a macro parameter is effectively *textual* substitution, whereas dereferencing a CMake variable is a semantic one.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">In other words, inside your macro, the text __ANDROID__ (when not expanded) never refers to the macro parameter. Macro parameters "don't exist" outside of expansion context. The `if(__ANDROID__)` bit therefore
always refers to the variable __ANDROID__, never to the macro parameter __ANDROID__.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">You still don't have to spell out the conditional as explicitly as you're doing it now, but you have to expand the parameter:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">macro(test __ANDROID__)<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> if(${__ANDROID__})<br>
message( "Included..... " ) <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> endif()<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">endmacro()<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">This is what the evaluation will look like based on how you call it:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">test(__ANDROID__) -> if(__ANDROID__) -> refers to the variable<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">set(__ANDROID__ 1)<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">test(${__ANDROID__}) -> if(1)<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">set(__ANDROID__ 0)<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">test(${__ANDROID__}) -> if(0)<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">test(OFF) -> if(OFF)<o:p></o:p></p>
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<div>
<p class="MsoNormal" style="margin-bottom:12.0pt">CMake macros have a lot of specific and potentially weird/counterintuitive behaviour. In general, you should always write your commands as functions and only resort to macros if you explicitly need their specific
behaviour.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Petr<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
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<div>
<div>
<p class="MsoNormal">On 30 January 2018 at 09:11, J Decker <<a href="mailto:d3ck0r@gmail.com" target="_blank">d3ck0r@gmail.com</a>> wrote:<o:p></o:p></p>
</div>
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<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm">
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<div>
<div>
<p class="MsoNormal">Why do I have to do <o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">if( ${M__ANDROID__} EQUAL 1 OR ${M__ANDROID__} STREQUAL "ON")<o:p></o:p></p>
</div>
</div>
<div>
<div>
<div>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:#222222">endif( ${M__ANDROID__} EQUAL 1 OR ${M__ANDROID__} STREQUAL "ON")<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><br>
in a macro like...<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">----------------------<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">set( __ANDROID__ 1 )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">macro( test __ANDROID__ )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"> if( ${__ANDROID__} EQUAL 1 OR ${__ANDROID__} STREQUAL "ON")<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> message( "Included..... " )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> endif( ${__ANDROID__} EQUAL 1 OR ${__ANDROID__} STREQUAL "ON")<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"> if( __ANDROID__ )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> message( "ALWAYS Included ${__ANDROID__}" )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> endif( __ANDROID__ )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">endmacro( test ) <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal" style="background:white"><span style="font-family:"Arial",sans-serif;color:#222222">test( __ANDROID__ )<o:p></o:p></span></p>
</div>
<p class="MsoNormal">test( ${__ANDROID__} )<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">test( OFF )<o:p></o:p></p>
</div>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">----------<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Output<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">Included.....<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">ALWAYS Included __ANDROID__<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Included.....<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">ALWAYS Included 1<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">ALWAYS Included OFF<o:p></o:p></p>
</div>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</div>
<p class="MsoNormal" style="margin-bottom:12.0pt">--<br>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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