Shape plugin resources not found in static builds

Using Qt 5.10.0 on iOS the radial gradients are broken. This is trivially reproducible by compiling the example shapes.

It seems that the problem is due to the shaders not being able to load:

Failed to find shader ":/qt-project.org/shapes/shaders/lineargradient.vert"
Failed to find shader ":/qt-project.org/shapes/shaders/lineargradient.frag"
QOpenGLShader::link: ERROR: Compiled vertex shader was corrupt.
ERROR: Compiled fragment shader was corrupt.