Fix crash with math inset with empty string.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@20284 a592a061-630c-0410-9148-cb99ea01b6c8

diff --git a/src/frontends/qt4/GuiPainter.cpp b/src/frontends/qt4/GuiPainter.cpp
index 465572b10ace214817c2088455fe953ae96e7030..b8a692602e347f40c7ecb2f897f1d57a1e99cf64 100644 (file)
--- a/src/frontends/qt4/GuiPainter.cpp
+++ b/src/frontends/qt4/GuiPainter.cpp
@@ -245,6 +245,9 @@ int GuiPainter::smallCapsText(int x, int y,
 int GuiPainter::text(int x, int y, docstring const & s,
                Font const & f)
 {
+       if (s.empty())
+               return 0;
+
        /* Caution: The following ucs4 to QString conversions work for symbol fonts
        only because they are no real conversions but simple casts in reality.
        When we want to draw a symbol or calculate the metrics we pass the position