Fix glfwGetInstanceProcAddress for static linking

README.md

@@ -107,6 +107,8 @@ information on what to include when reporting a bug.
 - Bugfix: Calling `glfwMaximizeWindow` on a full screen window was not ignored
 - Bugfix: `GLFW_INCLUDE_VULKAN` could not be combined with the corresponding
           OpenGL and OpenGL ES header macros
+- Bugfix: `glfwGetInstanceProcAddress` returned `NULL` for
+          `vkGetInstanceProcAddr` when `_GLFW_VULKAN_STATIC` was enabled
 - [Win32] Bugfix: Undecorated windows could not be iconified by the user (#861)
 - [Cocoa] Bugfix: Disabling window aspect ratio would assert (#852)
 - [Cocoa] Bugfix: Window creation failed to set first responder (#876,#883)

src/vulkan.c

@@ -240,7 +240,13 @@ GLFWAPI GLFWvkproc glfwGetInstanceProcAddress(VkInstance instance,
         return NULL;
 
     proc = (GLFWvkproc) vkGetInstanceProcAddr(instance, procname);
-#if !defined(_GLFW_VULKAN_STATIC)
+#if defined(_GLFW_VULKAN_STATIC)
+    if (!proc)
+    {
+        if (strcmp(procname, "vkGetInstanceProcAddr") == 0)
+            return (GLFWvkproc) vkGetInstanceProcAddr;
+    }
+#else
     if (!proc)
         proc = (GLFWvkproc) _glfw_dlsym(_glfw.vk.handle, procname);
 #endif