[gentoo-alt] Qt and pkg-config

[Sylvain Chevallier]

Hi all,
  I just solve a Qt issue that you may encounter. I use prefix on OS X.
  I try to compile sci-visualization/gnuplot with the support for Qt terminal (USE=qt4) and it failed during linking with the following error:

x86_64-apple-darwin12-g++  -march=nocona -O2 -pipe   -Wl,-dead_strip_dylibs -Wl,-rpath,/myprefix/gentoo/usr/lib/qt4 -Wl,-dead_strip_dylibs -lpng15 -o gnuplot alloc.o axis.o binary.o breaders.o color.o command.o contour.o datafile.o dynarray.o eval.o fit.o gadgets.o getcolor.o graph3d.o graphics.o help.o hidden3d.o history.o internal.o interpol.o matrix.o misc.o mouse.o parse.o plot.o plot2d.o plot3d.o pm3d.o readline.o save.o scanner.o set.o show.o specfun.o standard.o stats.o stdfn.o tables.o tabulate.o term.o time.o unset.o util.o util3d.o variable.o version.o  gp_cairo.o gp_cairo_helpers.o  qt_term.o qt_term_mac.o -lreadline  -lncurses  -lz -lgd -ljpeg -lz -liconv -ljpeg -lfreetype -lpng   QtNetwork QtSvg QtGui -F/myprefix/gentoo/usr/lib/qt4 -framework QtCore    -laquaterm  -framework Foundation -lz -lpangocairo-1.0 -lpango-1.0 -lgobject-2.0 -lcairo -lglib-2.0 -lintl   -framework Cocoa
x86_64-apple-darwin12-g++: QtNetwork : No such file or directory
x86_64-apple-darwin12-g++: QtSvg : No such file or directory
x86_64-apple-darwin12-g++: QtGui : No such file or directory
make[3]: *** [gnuplot] Error 1

  It turns out that pkg-config is responsible, in fact it is dev-util/pkgconf, a pkg-config "compatible" replacement that triggers the error by misinterpreting the Qt*.pc files. After an emerge -C pkgconf && emerge -1 pkgconfig, everything is back in order.

Best regards,
  Sylvain