I really hope that I'm not just screwing something up, but I've checked my code both against vulkan-tutorial.com and the InstancedSpheres lwjgl3 demo, and I'm doing the exact same thing. The symptom I'm having is that no triangles render if I use the depth compare op VK_COMPARE_OP_LESS but they do if I use VK_COMPARE_OP_GREATER (or _ALWAYS). But there is no difference when using _GREATER if I set the clear buffer to 0.0f or 1.0f or any other value; if the clear value was working setting the depth clear value to 1.0f really should result in no triangles being drawn. I ran the triangle demo (that doesn't use depth testing) which works and the instanced sphere demo (which doesn't work).
Here's the code i'm using:
VkClearValue.Buffer clearValue = VkClearValue.calloc(2);
try {
commandBeginInfo.sType(VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO);
commandBeginInfo.flags(VK_COMMAND_BUFFER_USAGE_SIMULTANEOUS_USE_BIT);
commandBeginInfo.pInheritanceInfo(null);
int ret = vkBeginCommandBuffer(cb, commandBeginInfo);
errorIfNecessary(ret, "Unable to begin recording in command buffers: ");
beginRenderPassInfo.sType(VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO);
beginRenderPassInfo.renderPass(renderPass);
beginRenderPassInfo.framebuffer(framebuffers[index]);
offset.x(0).y(0);
beginRenderPassInfo.renderArea().offset(offset);
beginRenderPassInfo.renderArea().extent(swapchainExtent);
clearValue.get(0).color().float32(0, 0).float32(1, 0f).float32(2, 0).float32(3, 1);
clearValue.get(1).depthStencil().depth(1.0f).stencil(0);
beginRenderPassInfo.pClearValues(clearValue);
vkCmdBeginRenderPass(cb, beginRenderPassInfo, VK_SUBPASS_CONTENTS_INLINE);
...
(I omitted the part which finishes recording the command buffers and frees the buffers.)
If I can do anything to help debug this (or to find out that it's somehow my fault), I'll be more than happy to run tests, etc. Thanks!
Can't see anything wrong with the above code. Could you prepare an MCVE (https://stackoverflow.com/help/mcve)?