The Android and Windows paths each have a skill; the desktop Linux one had only
a runner script and a README section, so it was the least discoverable of the
three despite being the one to reach for while iterating - it needs no device
and no GPU, and a single test group takes seconds rather than hours.
Records what the other two skills cannot: that the toolchain has to be GCC 13+
or Clang 20+ (Clang 18 reports __cpp_concepts as 201907L, which switches
libstdc++'s <expected> off and breaks the shader transpiler), that
EGL_PLATFORM=surfaceless is mandatory for DirectGLES and why the symptom points
at the wrong call, and which of this environment's results are MobileGL's own
versus artefacts of software rendering.
Also states the rule the other skills only imply: report Espryt and Magma
separately. They fail different cases, and one combined number hides which
backend a change moved.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DnW6wQYv2Pvrfisqak8UJu
run_cts_local.py and the mobilegl-desktop VK-GL-CTS target were both in the tree
with nothing describing how to reach them, so the only documented ways to run the
suite needed either an Android device or a Windows box with a GPU. The desktop
Linux path needs neither: lavapipe gives DirectVulkan a headless surface and
Mesa's surfaceless EGL gives DirectGLES a context, so a single test group can be
measured in seconds while working on it.
Records the two things that cost time to find. EGL_PLATFORM=surfaceless is
mandatory for DirectGLES - without a /dev/dri node Mesa fails eglInitialize on
the default display, and MobileGL surfaces that as EGL_BAD_ALLOC from
eglCreatePbufferSurface, which points at the wrong call entirely. And
DirectVulkan's default-framebuffer readback returns zeros here exactly as it does
on Adreno, so that defect is MobileGL's and reproducible without a phone.
The direct_state_access reference table is the measured baseline for the fixes in
this branch, so a later change has something to be compared against.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DnW6wQYv2Pvrfisqak8UJu