[VTR][LOG] Improved Unused Arg Warning Suppression

Previously, VTR's logging used `sizeof` static casted to void in order
to suppress the unused argument warning when we want logs to be a NOP.

The `sizeof` operator may have some strange affects, but since the code
is NOP anyways thats not a huge deal. The reason for this change is that
intellisence that use clangd flag this as a potential issue causing
warnings.

Also moved static variables from the header file of vtr_log to the
implementation. No functional change, but just prevents these variables
from being present and accessible in every file that uses vtr_log (which
is alot).

Author: AlexandreSinger

libs/libvtrutil/src/vtr_log.cpp

@@ -1,6 +1,7 @@
-#include <string>
-#include <fstream>
 #include <cstdarg>
+#include <fstream>
+#include <string>
+#include <unordered_set>
 
 #include "vtr_util.h"
 #include "vtr_log.h"
@@ -19,6 +20,9 @@ void set_log_file(const char* filename) {
 
 } // namespace vtr
 
+static std::unordered_set<std::string> warnings_to_suppress;
+static std::string noisy_warn_log_file;
+
 void add_warnings_to_suppress(std::string function_name) {
     warnings_to_suppress.insert(function_name);
 }

libs/libvtrutil/src/vtr_log.h

@@ -1,7 +1,6 @@
 #ifndef VTR_LOG_H
 #define VTR_LOG_H
 #include <tuple>
-#include <unordered_set>
 #include <string>
 
 /**
@@ -101,19 +100,14 @@
 /*
  * No-op version of logging macro which avoids unused parameter warnings.
  *
- * Note that to avoid unused parameter warnings we call sizeof() and cast
- * the result to void. sizeof is evaluated at compile time so there is no
- * run-time overhead.
- *
- * Also note the use of std::make_tuple to ensure all arguments in VA_ARGS
- * are used.
+ * Note the use of std::make_tuple to ensure all arguments in VA_ARGS are used.
  */
 #define VTR_LOGVF_NOP(expr, file, line, ...)                     \
     do {                                                         \
-        static_cast<void>(sizeof(expr));                         \
-        static_cast<void>(sizeof(file));                         \
-        static_cast<void>(sizeof(line));                         \
-        static_cast<void>(sizeof(std::make_tuple(__VA_ARGS__))); \
+        static_cast<void>(expr);                                 \
+        static_cast<void>(file);                                 \
+        static_cast<void>(line);                                 \
+        static_cast<void>(std::make_tuple(__VA_ARGS__));         \
     } while (false)
 
 // Debug logging macros
@@ -142,9 +136,6 @@ void set_log_file(const char* filename);
 
 } // namespace vtr
 
-static std::unordered_set<std::string> warnings_to_suppress;
-static std::string noisy_warn_log_file;
-
 /**
  * @brief The following data structure and functions allow to suppress noisy warnings and direct them into an external file, if specified.
  */