Re: Questions about configure/building regarding Qt and Lua

[sfeam <sf...@us...>]

On Thursday, 31 August 2017 16:05:48 Daniel J Sebald wrote:
> I upgraded to Mint 18.2 here, and I'm going through all the usually 
> system rebuilding...
> 
> Why does configure report:
> 
> checking for QT... yes
> configure: WARNING: The Qt terminal will use Qt5.
> 
> Is it simply because Qt5 is considered experimental support at this stage?

Just because the macro autotools provides to write something non-fatal
during configuration is AC_MSG_WARN.  You'd think they would provide
something blander like AC_MSG_JUST_IN_CASE_YOU_CARE, but no.
WARN is better than the alternatives ERROR or FAILURE.

> Also, when compiling I ran into a missing lrelease utility for Qt:
> 
> /bin/bash: /usr/lib/x86_64-linux-gnu/qt5/bin/lrelease: No such file or 
> directory
> Makefile:1282: recipe for target 'qtgnuplot_fr.qm' failed
> make[4]: *** [qtgnuplot_fr.qm] Error 127
> 
> Should configure check for that lrelease file that is being included? 

Sure.  But I don't know how to do that.  lrelease is not a library, so the
library test macros don't help. 

> It isn't too much trouble to find the package and install lrelease 
> (qttools5-dev-tools), but that package isn't automatically installed 
> with all the other Qt5 packages as a requirement.  

That seems more like a failure of the mint package dependencies than
something gnuplot's configure script is responsible for.
FWIW on my machines lrelease does not come in a separate *-dev-*
package.  It's in qttools5 proper.

> After installing 
> qttools5-dev-tools, compilation continues with 29 translations for Qt.
> 
> I then ran into this problem:
> 
> make[2]: Entering directory '/usr/local/src/gnuplot/gnuplot/build1/docs'
> lua5.2 /home/sebald/gnuplot/gnuplot/gnuplot/term/lua/gnuplot-tikz.lua 
> termhelp > gnuplot-tikz.help
> /bin/bash: lua5.2: command not found
> Makefile:979: recipe for target 'gnuplot-tikz.help' failed
> make[2]: *** [gnuplot-tikz.help] Error 127
> 
> which is of the same variety as the previous problem.  I had to install 
> lua5.2 package because it isn't a requirement for liblua5.2-dev package. 
>   Should configure check for the lua executable?

The configure script uses pkg-config to check for lua.
It checks for "lua", and if that fails it checks for "lua5.1", "lua5.2", "lua5.3".
So again it sounds like mint weirdness.  If pkg-config is reporting that you
have lua installed but really you do not, I would consider that a system
configuration error.

But also it's weird that bash is trying to run explicitly lua5.2.
Normally it just runs "lua" and that invokes the current installed version
whatever it is.  Can you pin down what script this is, exactly?  I don't
see any such script in the gnuplot source.

	Ethan