[OpenMP] Add void casts to silence unused variable warnings

These variables are used only in certain build configurations,
or marked with a todo comment indicating that they should be
used/checked/reported.

Differential Revision: https://reviews.llvm.org/D96582

GitOrigin-RevId: b3d84790faadaff95bd32ae9950205e044f6fce0
diff --git a/runtime/src/kmp_affinity.cpp b/runtime/src/kmp_affinity.cpp
index a94dbd1..2fff2c8 100644
--- a/runtime/src/kmp_affinity.cpp
+++ b/runtime/src/kmp_affinity.cpp
@@ -5059,6 +5059,7 @@
   return retval;
 
 #else
+  (void)retval;
 
   KMP_CPU_COPY((kmp_affin_mask_t *)(*mask), th->th.th_affin_mask);
   return 0;
diff --git a/runtime/src/kmp_atomic.cpp b/runtime/src/kmp_atomic.cpp
index a9d5257..99b4e84 100644
--- a/runtime/src/kmp_atomic.cpp
+++ b/runtime/src/kmp_atomic.cpp
@@ -2253,6 +2253,7 @@
 #define ATOMIC_CMPXCHG_CPT(TYPE_ID, OP_ID, TYPE, BITS, OP, GOMP_FLAG)          \
   ATOMIC_BEGIN_CPT(TYPE_ID, OP_ID, TYPE, TYPE)                                 \
   TYPE new_value;                                                              \
+  (void)new_value;                                                             \
   OP_GOMP_CRITICAL_CPT(TYPE, OP, GOMP_FLAG)                                    \
   OP_CMPXCHG_CPT(TYPE, BITS, OP)                                               \
   }
@@ -2261,6 +2262,7 @@
 #define ATOMIC_FIXED_ADD_CPT(TYPE_ID, OP_ID, TYPE, BITS, OP, GOMP_FLAG)        \
   ATOMIC_BEGIN_CPT(TYPE_ID, OP_ID, TYPE, TYPE)                                 \
   TYPE old_value, new_value;                                                   \
+  (void)new_value;                                                             \
   OP_GOMP_CRITICAL_CPT(TYPE, OP, GOMP_FLAG)                                    \
   /* OP used as a sign for subtraction: (lhs-rhs) --> (lhs+-rhs) */            \
   old_value = KMP_TEST_THEN_ADD##BITS(lhs, OP rhs);                            \
@@ -2561,6 +2563,7 @@
 #define ATOMIC_CMPX_L_CPT(TYPE_ID, OP_ID, TYPE, BITS, OP, GOMP_FLAG)           \
   ATOMIC_BEGIN_CPT(TYPE_ID, OP_ID, TYPE, TYPE)                                 \
   TYPE new_value;                                                              \
+  (void)new_value;                                                             \
   OP_GOMP_CRITICAL_L_CPT(= *lhs OP, GOMP_FLAG)                                 \
   OP_CMPXCHG_CPT(TYPE, BITS, OP)                                               \
   }
@@ -2655,6 +2658,7 @@
 #define MIN_MAX_COMPXCHG_CPT(TYPE_ID, OP_ID, TYPE, BITS, OP, GOMP_FLAG)        \
   ATOMIC_BEGIN_CPT(TYPE_ID, OP_ID, TYPE, TYPE)                                 \
   TYPE new_value, old_value;                                                   \
+  (void)new_value;                                                             \
   if (*lhs OP rhs) {                                                           \
     GOMP_MIN_MAX_CRITSECT_CPT(OP, GOMP_FLAG)                                   \
     MIN_MAX_CMPXCHG_CPT(TYPE, BITS, OP)                                        \
@@ -2713,6 +2717,7 @@
 #define ATOMIC_CMPX_EQV_CPT(TYPE_ID, OP_ID, TYPE, BITS, OP, GOMP_FLAG)         \
   ATOMIC_BEGIN_CPT(TYPE_ID, OP_ID, TYPE, TYPE)                                 \
   TYPE new_value;                                                              \
+  (void)new_value;                                                             \
   OP_GOMP_CRITICAL_EQV_CPT(^= (TYPE) ~, GOMP_FLAG) /* send assignment */       \
   OP_CMPXCHG_CPT(TYPE, BITS, OP)                                               \
   }
@@ -2941,6 +2946,7 @@
 #define ATOMIC_CMPXCHG_CPT_REV(TYPE_ID, OP_ID, TYPE, BITS, OP, GOMP_FLAG)      \
   ATOMIC_BEGIN_CPT(TYPE_ID, OP_ID, TYPE, TYPE)                                 \
   TYPE new_value;                                                              \
+  (void)new_value;                                                             \
   OP_GOMP_CRITICAL_CPT_REV(TYPE, OP, GOMP_FLAG)                                \
   OP_CMPXCHG_CPT_REV(TYPE, BITS, OP)                                           \
   }
@@ -3261,6 +3267,7 @@
 #define ATOMIC_CMPXCHG_SWP(TYPE_ID, TYPE, BITS, GOMP_FLAG)                     \
   ATOMIC_BEGIN_SWP(TYPE_ID, TYPE)                                              \
   TYPE old_value;                                                              \
+  (void)old_value;                                                             \
   GOMP_CRITICAL_SWP(GOMP_FLAG)                                                 \
   CMPXCHG_SWP(TYPE, BITS)                                                      \
   }
diff --git a/runtime/src/kmp_io.cpp b/runtime/src/kmp_io.cpp
index 4e6ea6a..2379162 100644
--- a/runtime/src/kmp_io.cpp
+++ b/runtime/src/kmp_io.cpp
@@ -101,6 +101,7 @@
 
       DWORD err = GetLastError();
       // TODO: output error somehow (maybe message box)
+      (void)err;
       __kmp_stdout = NULL;
 
     } else {
@@ -112,6 +113,7 @@
 
       DWORD err = GetLastError();
       // TODO: output error somehow (maybe message box)
+      (void)err;
       __kmp_stderr = NULL;
 
     } else {
diff --git a/runtime/src/kmp_tasking.cpp b/runtime/src/kmp_tasking.cpp
index 876cd25..dde7a96 100644
--- a/runtime/src/kmp_tasking.cpp
+++ b/runtime/src/kmp_tasking.cpp
@@ -4157,6 +4157,7 @@
       }
     }
 #else
+    (void)taskdata;
     retval = *(kmp_int64 *)((char *)task + lower_offset);
 #endif // defined(KMP_GOMP_COMPAT)
     return retval;
diff --git a/runtime/src/z_Windows_NT_util.cpp b/runtime/src/z_Windows_NT_util.cpp
index 2e9484b..429ffb6 100644
--- a/runtime/src/z_Windows_NT_util.cpp
+++ b/runtime/src/z_Windows_NT_util.cpp
@@ -671,6 +671,7 @@
     BOOL ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
                                      GET_MODULE_HANDLE_EX_FLAG_PIN,
                                  (LPCTSTR)&__kmp_serial_initialize, &h);
+    (void)ret;
     KMP_DEBUG_ASSERT2(h && ret, "OpenMP RTL cannot find itself loaded");
     SetErrorMode(err_mode); // Restore error mode
     KA_TRACE(10, ("__kmp_runtime_initialize: dynamic library pinned\n"));
@@ -830,6 +831,7 @@
     __kmp_xproc = info.dwNumberOfProcessors;
   }
 #else
+  (void)kernel32;
   GetSystemInfo(&info);
   __kmp_xproc = info.dwNumberOfProcessors;
 #endif /* KMP_GROUP_AFFINITY */