[OpenMP] libomptarget: eliminate compiler warnings at build

[sdmitriev]

Summary

Small change to silence compiler warnings about casing pointer to object to a pointer to function like this

.../llvm/projects/openmp/libomptarget/src/omptarget.cpp: In member function 'void RTLsTy::LoadRTLs()':
.../llvm/projects/openmp/libomptarget/src/omptarget.cpp:318:57: warning: ISO C++ forbids casting between pointer-to-function and pointer-to-object [-Wpedantic]

dynlib_handle, "__tgt_rtl_is_valid_binary")))
                                          ^

[grokos]

Looks good. Can you commit the patch?

[sdmitriev]

I do not have commit access, so I cannot commit it myself. Can you please check it in?

[Hahnfeld]

Because I've seen this on other revisions as well: Please always subscribe the relevant mailing list!

libomptarget/plugins/generic-elf-64bit/src/rtl.cpp

int32_t __tgt_rtl_run_target_team_region(int32_t device_id, void *tgt_entry_ptr,
 
   assert(status == FFI_OK && "Unable to prepare target launch!");
 
   if (status != FFI_OK)
     return OFFLOAD_FAIL;
 
   DP("Running entry point at " DPxMOD "...\n", DPxPTR(tgt_entry_ptr));
 
-  ffi_call(&cif, FFI_FN(tgt_entry_ptr), NULL, &args[0]);
+  void (*entry)(void);
+  *((void**) &entry) = tgt_entry_ptr;
+  ffi_call(&cif, entry, NULL, &args[0]);
   return OFFLOAD_SUCCESS;
 }
 
 int32_t __tgt_rtl_run_target_region(int32_t device_id, void *tgt_entry_ptr,
     void **tgt_args, ptrdiff_t *tgt_offsets, int32_t arg_num) {
   // use one team and one thread.
   return __tgt_rtl_run_target_team_region(device_id, tgt_entry_ptr, tgt_args,
       tgt_offsets, arg_num, 1, 1, 0);
 }
 
 #ifdef __cplusplus
 }
 #endif

libomptarget/src/omptarget.cpp

for (auto *Name : RTLNames) {
 
     R.LibraryHandler = dynlib_handle;
     R.isUsed = false;
 
 #ifdef OMPTARGET_DEBUG
     R.RTLName = Name;
 #endif
 
-    if (!(R.is_valid_binary = (RTLInfoTy::is_valid_binary_ty *)dlsym(
+    if (!(*((void**) &R.is_valid_binary) = dlsym(
               dynlib_handle, "__tgt_rtl_is_valid_binary")))
       continue;
-    if (!(R.number_of_devices = (RTLInfoTy::number_of_devices_ty *)dlsym(
+    if (!(*((void**) &R.number_of_devices) = dlsym(
               dynlib_handle, "__tgt_rtl_number_of_devices")))
       continue;
-    if (!(R.init_device = (RTLInfoTy::init_device_ty *)dlsym(
+    if (!(*((void**) &R.init_device) = dlsym(
               dynlib_handle, "__tgt_rtl_init_device")))
       continue;
-    if (!(R.load_binary = (RTLInfoTy::load_binary_ty *)dlsym(
+    if (!(*((void**) &R.load_binary) = dlsym(
               dynlib_handle, "__tgt_rtl_load_binary")))
       continue;
-    if (!(R.data_alloc = (RTLInfoTy::data_alloc_ty *)dlsym(
+    if (!(*((void**) &R.data_alloc) = dlsym(
               dynlib_handle, "__tgt_rtl_data_alloc")))
       continue;
-    if (!(R.data_submit = (RTLInfoTy::data_submit_ty *)dlsym(
+    if (!(*((void**) &R.data_submit) = dlsym(
               dynlib_handle, "__tgt_rtl_data_submit")))
       continue;
-    if (!(R.data_retrieve = (RTLInfoTy::data_retrieve_ty *)dlsym(
+    if (!(*((void**) &R.data_retrieve) = dlsym(
               dynlib_handle, "__tgt_rtl_data_retrieve")))
       continue;
-    if (!(R.data_delete = (RTLInfoTy::data_delete_ty *)dlsym(
+    if (!(*((void**) &R.data_delete) = dlsym(
               dynlib_handle, "__tgt_rtl_data_delete")))
       continue;
-    if (!(R.run_region = (RTLInfoTy::run_region_ty *)dlsym(
+    if (!(*((void**) &R.run_region) = dlsym(
               dynlib_handle, "__tgt_rtl_run_target_region")))
       continue;
-    if (!(R.run_team_region = (RTLInfoTy::run_team_region_ty *)dlsym(
+    if (!(*((void**) &R.run_team_region) = dlsym(
               dynlib_handle, "__tgt_rtl_run_target_team_region")))
       continue;
 
     // No devices are supported by this RTL?
     if (!(R.NumberOfDevices = R.number_of_devices())) {
       DP("No devices supported in this RTL\n");
       continue;
     }