This test began failing with a seemingly unrelated piglit commit:
7c8ee3f0f13d8a2323aa26f4a85128c6191545b0
Author:     Eric Engestrom <eric.engestrom@intel.com>

util: simplify string duplication logic

Suggested-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>


stdout

/tmp/build_root/m64/lib/piglit/bin/arb_gpu_shader5-xfb-streams-without-invocations -auto -fbo
piglit: debug: Requested an OpenGL 3.2 Core Context, and received a matching 4.5 context

stderr

Failed to compile vertex shader: 0:8(1): error: syntax error, unexpected '[', expecting $end

source:
#version 450

void main() {
     gl_Position = vec4(0.0);
}


[