[libomptarget] Initialize reference parameter IsNew within Device::getOrAllocTgtPtr

[ronlieb]

Summary

The two locals IsNew and Pointer_IsNew were uninitialized at declaration, and then passed by
reference to Device.getOrAllocTgtPtr which in turn did not assign on all
paths within the function. This resulted in occasional runtime failures in one application.
 Device::getOrAllocTgtPtr will now initialize IsNew to false on entry to function.

[grokos]

I think it would look better if we initialized those variables inside Device::getOrAllocTgtPtr - the caller should not assume any default value. That's also what happens in target_data_end with the IsLast variable, it is initialized inside Device::getTgtPtrBegin.

[ronlieb]

Modified patch to assign to IsNew on entry to Device::getOrAllocTgtPtr

[grokos]

LGTM.

openmp/libomptarget/src/omptarget.cpp

if (member_of(arg_types[i]) < 0 && next_i < arg_num &&
             "\n", padding, DPxPTR(HstPtrBegin));
         HstPtrBegin = (char *) HstPtrBegin - padding;
         data_size += padding;
       }
     }
 
     // Address of pointer on the host and device, respectively.
     void *Pointer_HstPtrBegin, *Pointer_TgtPtrBegin;
-    bool IsNew, Pointer_IsNew;
+    bool IsNew = false, Pointer_IsNew = false;
     bool IsHostPtr = false;
     bool IsImplicit = arg_types[i] & OMP_TGT_MAPTYPE_IMPLICIT;
     // Force the creation of a device side copy of the data when:
     // a close map modifier was associated with a map that contained a to.
     bool HasCloseModifier = arg_types[i] & OMP_TGT_MAPTYPE_CLOSE;
     // UpdateRef is based on MEMBER_OF instead of TARGET_PARAM because if we
     // have reached this point via __tgt_target_data_begin and not __tgt_target
     // then no argument is marked as TARGET_PARAM ("omp target data map" is not