Avoid the Apple OpenGL null-fence crash during precache (#30)

glDeleteBuffers and glWaitSync on a failed fence both fault in
GLDFenceRec::getStatus on Apple's GL/Metal translator. Finish and
unbind before deleting buffers, skip a null upload fence, and resize
depth targets with the unsized format Apple accepts.

3 files changed, 63 insertions, 18 deletions

diff --git a/indra/llrender/llimagegl.cpp b/indra/llrender/llimagegl.cpp
index 1d51c6741c..82bc00fe7a 100644
--- a/indra/llrender/llimagegl.cpp
+++ b/indra/llrender/llimagegl.cpp
@@ -1839,9 +1839,16 @@ void LLImageGL::syncToMainThread(LLGLuint new_tex_name)
             // wait for texture upload to finish before notifying main thread
             // upload is complete
             auto sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
-            glFlush();
-            glClientWaitSync(sync, 0, GL_TIMEOUT_IGNORED);
-            glDeleteSync(sync);
+            if (sync)
+            {
+                glFlush();
+                glClientWaitSync(sync, 0, GL_TIMEOUT_IGNORED);
+                glDeleteSync(sync);
+            }
+            else
+            {
+                glFinish();
+            }
         }
         else
         {
@@ -1851,20 +1858,29 @@ void LLImageGL::syncToMainThread(LLGLuint new_tex_name)
             glFlush();
             auto sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
             glFlush();
-            LL::WorkQueue::postMaybe(
-                mMainQueue,
-                [=]()
-                {
-                    LL_PROFILE_ZONE_NAMED("cglt - wait sync");
-                    {
-                        LL_PROFILE_ZONE_NAMED("glWaitSync");
-                        glWaitSync(sync, 0, GL_TIMEOUT_IGNORED);
-                    }
+            if (sync)
+            {
+                LL::WorkQueue::postMaybe(
+                    mMainQueue,
+                    [=]()
                     {
-                        LL_PROFILE_ZONE_NAMED("glDeleteSync");
-                        glDeleteSync(sync);
-                    }
-                });
+                        LL_PROFILE_ZONE_NAMED("cglt - wait sync");
+                        {
+                            LL_PROFILE_ZONE_NAMED("glWaitSync");
+                            glWaitSync(sync, 0, GL_TIMEOUT_IGNORED);
+                        }
+                        {
+                            LL_PROFILE_ZONE_NAMED("glDeleteSync");
+                            glDeleteSync(sync);
+                        }
+                    });
+            }
+            else
+            {
+                // glFenceSync failed. glWaitSync(0) is dispatched to Apple's
+                // OpenGL thread, which faults in GLDFenceRec::getStatus.
+                glFinish();
+            }
         }
     }
 
diff --git a/indra/llrender/llrendertarget.cpp b/indra/llrender/llrendertarget.cpp
index ebdc609f94..dcee340a71 100644
--- a/indra/llrender/llrendertarget.cpp
+++ b/indra/llrender/llrendertarget.cpp
@@ -95,7 +95,15 @@ void LLRenderTarget::resize(U32 resx, U32 resy)
     {
         gGL.getTexUnit(0)->bindManual(mUsage, mDepth);
         U32 internal_type = LLTexUnit::getInternalType(mUsage);
-        LLImageGL::setManualImage(internal_type, 0, GL_DEPTH_COMPONENT24, mResX, mResY, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, NULL, false);
+        // Apple's GL rejects sized GL_DEPTH_COMPONENT24 with GL_UNSIGNED_INT.
+#if LL_DARWIN
+        const U32 depth_internal = GL_DEPTH_COMPONENT;
+#else
+        const U32 depth_internal = GL_DEPTH_COMPONENT24;
+#endif
+        glGetError();
+        LLImageGL::setManualImage(internal_type, 0, depth_internal, mResX, mResY, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, NULL, false);
+        glGetError();
 
         sBytesAllocated += pix_diff*4;
     }
diff --git a/indra/llrender/llvertexbuffer.cpp b/indra/llrender/llvertexbuffer.cpp
index 8a73a68c54..a827927809 100644
--- a/indra/llrender/llvertexbuffer.cpp
+++ b/indra/llrender/llvertexbuffer.cpp
@@ -315,7 +315,28 @@ static void delete_buffers(S32 count, GLuint* buffers)
 
         if (!sFreeList[idx].empty())
         {
-            glDeleteBuffers((GLsizei)sFreeList[idx].size(), sFreeList[idx].data());
+            if (gGLManager.mIsApple)
+            {
+                // Apple's GL/Metal translator crashes in GLDFenceRec::getStatus
+                // (null fence, fault at +0x24) when glDeleteBuffers waits on a
+                // sync that was never created. Unbind and finish first.
+                glBindBuffer(GL_ARRAY_BUFFER, 0);
+                glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+                LLVertexBuffer::sGLRenderBuffer = 0;
+                LLVertexBuffer::sGLRenderIndices = 0;
+                glFinish();
+                for (GLuint name : sFreeList[idx])
+                {
+                    if (name)
+                    {
+                        glDeleteBuffers(1, &name);
+                    }
+                }
+            }
+            else
+            {
+                glDeleteBuffers((GLsizei)sFreeList[idx].size(), sFreeList[idx].data());
+            }
             sFreeList[idx].resize(0);
         }
     }