Skip to content

dynamic vulkan loading on apple platforms, honor VK_DRIVER_FILES env #6499

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
nihui merged 15 commits into from
Jan 11, 2026
+182 −180
Merged

dynamic vulkan loading on apple platforms, honor VK_DRIVER_FILES env #6499

Changes from 2 commits
Commits
Show all changes
15 commits
Select commit Hold shift + click to select a range
192f33f
dynamic vulkan loading on apple platforms, honor VK_DRIVER_FILES env
nihui Jan 9, 2026
211c927
f
nihui Jan 9, 2026
9845873
Update Vulkan library path in macOS workflow
nihui Jan 9, 2026
edd8a0d
update moltenvk
nihui Jan 9, 2026
3902b3d
test2
nihui Jan 9, 2026
de22379
w
nihui Jan 9, 2026
e2b7280
weak import
nihui Jan 9, 2026
117442d
r
nihui Jan 9, 2026
372d5e2
link stub
nihui Jan 9, 2026
e4d0853
z
nihui Jan 9, 2026
2700267
use tbd
nihui Jan 10, 2026
effe5d8
ppp
nihui Jan 10, 2026
96b8aae
Merge branch 'master' into enhance-apple-vulkan-loader
nihui Jan 11, 2026
293d16f
doc
nihui Jan 11, 2026
42bbeb2
f
nihui Jan 11, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
184 changes: 93 additions & 91 deletions src/simplevk.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -27,10 +27,8 @@
#endif

#if __APPLE__

// always use static vulkan linkage on apple platform
// static vulkan linkage on apple platform as fallback
extern "C" VKAPI_ATTR PFN_vkVoidFunction VKAPI_CALL vkGetInstanceProcAddr(VkInstance instance, const char* pName);

#endif

namespace ncnn {
Expand All @@ -43,28 +41,78 @@ PFN_vkEnumerateInstanceExtensionProperties vkEnumerateInstanceExtensionPropertie
PFN_vkCreateInstance vkCreateInstance = 0;
PFN_vkEnumerateInstanceLayerProperties vkEnumerateInstanceLayerProperties = 0;

#if __APPLE__

int load_vulkan_driver(const char* /*driver_path*/)
static std::string get_driver_path_from_icd(const char* icd_path)
{
unload_vulkan_driver();
FILE* fp = fopen(icd_path, "rb");
if (!fp)
return std::string();

vkGetInstanceProcAddr = ::vkGetInstanceProcAddr;
vkEnumerateInstanceExtensionProperties = (PFN_vkEnumerateInstanceExtensionProperties)vkGetInstanceProcAddr(NULL, "vkEnumerateInstanceExtensionProperties");
vkCreateInstance = (PFN_vkCreateInstance)vkGetInstanceProcAddr(NULL, "vkCreateInstance");
vkEnumerateInstanceLayerProperties = (PFN_vkEnumerateInstanceLayerProperties)vkGetInstanceProcAddr(NULL, "vkEnumerateInstanceLayerProperties");
return 0;
std::string driver_path;

char line[256];
while (!feof(fp))
{
char* s = fgets(line, 256, fp);
if (!s)
break;

// "library_path": "path to driver library",
char path[256];
int nscan = sscanf(line, " \"library_path\" : \"%255[^\"]\"", path);
Comment on lines +52 to +61
Copy link

Copilot AI Jan 10, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The fixed-size buffers 'line' and 'path' (both 256 bytes) could potentially overflow if the ICD JSON file contains very long library paths. While the sscanf format string limits to 255 characters, JSON files in the wild could have paths longer than this. Consider using dynamic allocation or a larger buffer size, or add proper error handling for truncated paths.

Copilot uses AI. Check for mistakes.
if (nscan == 1)
{
if (path[0] == '.' || (path[0] != '/' && !strchr(path, ':') && (strchr(path, '/') || strchr(path, '\\'))))
Copy link

Copilot AI Jan 10, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The path detection logic has a complex condition that may not correctly identify all relative paths. The condition path[0] != '/' && !strchr(path, ':') && (strchr(path, '/') || strchr(path, '\\')) will miss paths like "subdir/file" that don't start with '.' but are still relative. Consider simplifying the logic: paths starting with '.' are relative, paths starting with '/' (or containing ':' on Windows for absolute paths like C:) are absolute, and all other paths could be treated as filenames that should be searched relative to the ICD file location or in system paths.

Suggested change
if (path[0] == '.' || (path[0] != '/' && !strchr(path, ':') && (strchr(path, '/') || strchr(path, '\\'))))
bool is_absolute = (path[0] == '/' || path[0] == '\\' || strchr(path, ':'));
if (!is_absolute)

Copilot uses AI. Check for mistakes.
{
// relative to the icd file path
std::string icd_dir = icd_path;
size_t dirpos = icd_dir.find_last_of("/\\");
if (dirpos != std::string::npos)
{
icd_dir = icd_dir.substr(0, dirpos + 1);
}
else
{
icd_dir = "./";
}

driver_path = icd_dir + path;
}
else
{
// filename or absolute path
driver_path = path;
}

break;
}
}

fclose(fp);

return driver_path;
}

void unload_vulkan_driver()
static std::string get_driver_path_from_icd_env()
{
vkGetInstanceProcAddr = 0;
vkEnumerateInstanceExtensionProperties = 0;
vkCreateInstance = 0;
vkEnumerateInstanceLayerProperties = 0;
const char* icd_path = getenv("VK_ICD_FILENAMES");
if (!icd_path)
{
icd_path = getenv("VK_DRIVER_FILES");
if (!icd_path)
return std::string();
}

return get_driver_path_from_icd(icd_path);
}

#else // __APPLE__
static std::string get_driver_path_from_ncnn_env()
{
const char* driver_path = getenv("NCNN_VULKAN_DRIVER");
if (!driver_path)
return std::string();

return std::string(driver_path);
}

#if defined _WIN32
static HMODULE g_libvulkan = 0;
Expand Down Expand Up @@ -134,75 +182,6 @@ static hwvulkan_device_t* g_hvkdi = 0;
#endif
#endif

static std::string get_driver_path_from_icd(const char* icd_path)
{
FILE* fp = fopen(icd_path, "rb");
if (!fp)
return std::string();

std::string driver_path;

char line[256];
while (!feof(fp))
{
char* s = fgets(line, 256, fp);
if (!s)
break;

// "library_path": "path to driver library",
char path[256];
int nscan = sscanf(line, " \"library_path\" : \"%255[^\"]\"", path);
if (nscan == 1)
{
if (path[0] == '.' || (path[0] != '/' && !strchr(path, ':') && (strchr(path, '/') || strchr(path, '\\'))))
{
// relative to the icd file path
std::string icd_dir = icd_path;
size_t dirpos = icd_dir.find_last_of("/\\");
if (dirpos != std::string::npos)
{
icd_dir = icd_dir.substr(0, dirpos + 1);
}
else
{
icd_dir = "./";
}

driver_path = icd_dir + path;
}
else
{
// filename or absolute path
driver_path = path;
}

break;
}
}

fclose(fp);

return driver_path;
}

static std::string get_driver_path_from_icd_env()
{
const char* icd_path = getenv("VK_ICD_FILENAMES");
if (!icd_path)
return std::string();

return get_driver_path_from_icd(icd_path);
}

static std::string get_driver_path_from_ncnn_env()
{
const char* driver_path = getenv("NCNN_VULKAN_DRIVER");
if (!driver_path)
return std::string();

return std::string(driver_path);
}

#if defined _WIN32
static std::string search_file(const std::string& dirpath, const std::string& needle)
{
Expand Down Expand Up @@ -305,12 +284,14 @@ static int load_vulkan_linux(const char* driver_path)
#endif

void* libvulkan = dlopen(libpath, RTLD_LOCAL | RTLD_NOW);
#if !__APPLE__
if (!libvulkan)
{
#if __APPLE__
libvulkan = dlopen("libvulkan.1.dylib", RTLD_LOCAL | RTLD_NOW);
#else
libvulkan = dlopen("libvulkan.so.1", RTLD_LOCAL | RTLD_NOW);
}
#endif
}
if (!libvulkan)
{
NCNN_LOGE("dlopen failed %s", dlerror());
Expand Down Expand Up @@ -356,6 +337,17 @@ static int load_vulkan_linux(const char* driver_path)
return 0;
}

#if __APPLE__
static int load_vulkan_apple_moltenvk()
{
vkGetInstanceProcAddr = ::vkGetInstanceProcAddr;
vkEnumerateInstanceExtensionProperties = (PFN_vkEnumerateInstanceExtensionProperties)vkGetInstanceProcAddr(NULL, "vkEnumerateInstanceExtensionProperties");
vkCreateInstance = (PFN_vkCreateInstance)vkGetInstanceProcAddr(NULL, "vkCreateInstance");
vkEnumerateInstanceLayerProperties = (PFN_vkEnumerateInstanceLayerProperties)vkGetInstanceProcAddr(NULL, "vkEnumerateInstanceLayerProperties");
return 0;
}
#endif // __APPLE__

#if defined __ANDROID__
static int load_vulkan_android(const char* driver_path)
{
Expand Down Expand Up @@ -535,6 +527,11 @@ int load_vulkan_driver(const char* driver_path)
"/vendor/lib/egl/libGLES_mali.so"
#endif
};
#elif __APPLE__
const char* well_known_path[] = {
"libMoltenVK.dylib",
Copy link

Copilot AI Jan 10, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The well-known path entry "libvulkan_kosmickrisp.dylib" appears to be a non-standard or test/development library name. If this is a legitimate Vulkan implementation, it should be documented. If it's for testing purposes only, consider adding a comment explaining its purpose. The unusual name "kosmickrisp" may confuse future maintainers.

Suggested change
"libMoltenVK.dylib",
"libMoltenVK.dylib",
// Non-standard/internal Vulkan implementation used as an additional fallback on Apple platforms.

Copilot uses AI. Check for mistakes.
"libvulkan_kosmickrisp.dylib"
};
#else
const char* well_known_path[] = {
"libGLX_nvidia.so.0",
Expand Down Expand Up @@ -565,6 +562,13 @@ int load_vulkan_driver(const char* driver_path)
break;
}
}
#if __APPLE__
if (ret != 0)
{
// sixth try, load from static linked moltenvk
ret = load_vulkan_apple_moltenvk();
}
#endif // __APPLE__

return ret;
}
Expand Down Expand Up @@ -602,8 +606,6 @@ void unload_vulkan_driver()
#endif // _WIN32
}

#endif // __APPLE__

} // namespace ncnn

#endif // NCNN_SIMPLEVK
Expand Down
Loading