From e51362eb8d2517999aed5ee21c555b8dd3eafd55 Mon Sep 17 00:00:00 2001
From: Mike Beaton <mjsbeaton@gmail.com>
Date: Wed, 13 Dec 2023 23:14:07 +0000
Subject: [PATCH] DebugLib: Simplify DEBUG and ASSERT macros used when
 MDEPKG_NDEBUG is defined

The variants provided when MDEPKG_NDEBUG is defined will be optimised
away in RELEASE builds, but by referencing the argument (or argument list,
in the case of DEBUG) avoid unused variable errors from valid debug code,
for example when STATIC variables are used only in DEBUG statements.
---
 MdePkg/Include/Library/DebugLib.h | 23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/MdePkg/Include/Library/DebugLib.h b/MdePkg/Include/Library/DebugLib.h
index d811fd3479..1b0e25c646 100644
--- a/MdePkg/Include/Library/DebugLib.h
+++ b/MdePkg/Include/Library/DebugLib.h
@@ -408,7 +408,7 @@ UnitTestDebugAssert (
 #else
 #define ASSERT(Expression)       \
     do {                           \
-      if ((FALSE)) {               \
+      if (FALSE) {                 \
         (VOID) (Expression);       \
       }                            \
     } while (FALSE)
@@ -433,18 +433,13 @@ UnitTestDebugAssert (
         _DEBUG (Expression);       \
       }                            \
     } while (FALSE)
-#elif defined (__GNUC__) || defined (__clang__)
-#define DEBUG(Expression)                                \
-    do {                                                   \
-      _Pragma("GCC diagnostic push")                       \
-      _Pragma("GCC diagnostic ignored \"-Wunused-value\"") \
-      if ((FALSE)) {                                       \
-        (VOID) Expression;                                 \
-      }                                                    \
-      _Pragma("GCC diagnostic pop")                        \
-    } while (FALSE)
 #else
-#define DEBUG(Expression)
+#define DEBUG(Expression)        \
+    do {                           \
+      if (FALSE) {                 \
+        _DEBUG (Expression);       \
+      }                            \
+    } while (FALSE)
 #endif
 
 /**
@@ -472,7 +467,7 @@ UnitTestDebugAssert (
 #else
 #define ASSERT_EFI_ERROR(StatusParameter)                                             \
     do {                                                                                \
-      if ((FALSE)) {                                                                    \
+      if (FALSE) {                                                                      \
         (VOID) (StatusParameter);                                                       \
       }                                                                                 \
     } while (FALSE)
@@ -504,7 +499,7 @@ UnitTestDebugAssert (
 #else
 #define ASSERT_RETURN_ERROR(StatusParameter)                          \
     do {                                                                \
-      if ((FALSE)) {                                                    \
+      if (FALSE) {                                                      \
         (VOID) (StatusParameter);                                       \
       }                                                                 \
     } while (FALSE)