Fix memory leaks related to layers and vendor icds

loader/icd.c

@@ -210,6 +210,15 @@ void khrIcdVendorAdd(const char *libraryName)
     }
 }
 
+void khrIcdVendorCleanup() {
+    KHRicdVendor* nextVendor = NULL;
+    while (khrIcdVendors) {
+        nextVendor = khrIcdVendors->next;
+        free(khrIcdVendors);
+        khrIcdVendors = nextVendor;
+    }
+}
+
 #if defined(CL_ENABLE_LAYERS)
 void khrIcdLayerAdd(const char *libraryName)
 {
@@ -345,6 +354,15 @@ void khrIcdLayerAdd(const char *libraryName)
         free(layer);
     }
 }
+
+void khrIcdLayerCleanup() {
+    struct KHRLayer* nextLayer = NULL;
+    while (khrFirstLayer) {
+        nextLayer = khrFirstLayer->next;
+        free(khrFirstLayer);
+        khrFirstLayer = nextLayer;
+    }
+}
 #endif // defined(CL_ENABLE_LAYERS)
 
 // Get next file or dirname given a string list or registry key path.

loader/icd.h

@@ -152,12 +152,18 @@ void khrIcdVendorsEnumerateEnv(void);
 // add a vendor's implementation to the list of libraries
 void khrIcdVendorAdd(const char *libraryName);
 
+// cleanup a list of vendor icds
+void khrIcdVendorCleanup();
+
 // read layers from environment variables
 void khrIcdLayersEnumerateEnv(void);
 
 // add a layer to the layer chain
 void khrIcdLayerAdd(const char *libraryName);
 
+// cleanup a layer chain
+void khrIcdLayerCleanup();
+
 // dynamically load a library.  returns NULL on failure
 // n.b, this call is OS-specific
 void *khrIcdOsLibraryLoad(const char *libraryName);

loader/linux/icd_linux.c

@@ -260,3 +260,8 @@ void khrIcdOsLibraryUnload(void *library)
 {
     dlclose(library);
 }
+
+void __attribute__((destructor)) khrIcdGlobalDestructor() {
+    khrIcdVendorCleanup();
+    khrIcdLayerCleanup();
+}

loader/windows/icd_windows.c

@@ -443,3 +443,11 @@ void khrIcdOsLibraryUnload(void *library)
 {
     FreeLibrary( (HMODULE)library);
 }
+
+BOOL APIENTRY DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) {
+    if (fdwReason == DLL_PROCESS_DETACH) {
+        khrIcdVendorCleanup();
+        khrIcdLayerCleanup();
+    }
+    return TRUE;
+}