From 80c73c39231df17ca066483c4bee5030d2f6c65f Mon Sep 17 00:00:00 2001
From: Mikhail Krichanov <mikhailkrichanov@gmail.com>
Date: Mon, 22 Jul 2024 12:37:00 +0300
Subject: [PATCH] MdePkg: DebugLib: Compilation fix for clang-13
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Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3704

build -a X64 -t CLANG38 -b RELEASE -p OvmfPkg/OvmfPkgX64.dsc
results in
UDK/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c:1284:31:
error: variable 'Status' set but not used
[-Werror,-Wunused-but-set-variable]

Signed-off-by: Mikhail Krichanov <krichanov@ispras.ru>

MdePkg/DebugLib(PerformanceLib): Fix "unused-but-set-variable" warning

The current definitions of DEBUG_CODE_BEGIN() and DEBUG_CODE_END() use
the local
variable __DebugCodeLocal as an attempt to track parity. If
DEBUG_CODE_END() is
used without a preceding DEBUG_CODE_BEGIN(), __DebugCodeLocal will not
have been
declared and a compilation error will be issued. The mutations of the
variable
are not used to track nesting or such. As the value of this variable is
never
actually used, recent Clang versions issue a "unused-but-set-variable"
warning
for it.

To solve this, re-define __DebugCodeLocal as a BOOLEAN that is always
FALSE and
use it in a do-while loop condition as done explicitly in many places.
Like the
previous solution, DEBUG_CODE_END() cannot be used without
DEBUG_CODE_BEGIN(),
as __DebugCodeLocal will be not have been defined.

Signed-off-by: Marvin Häuser <mhaeuser@posteo.de>
---
 .../AArch64/DefaultExceptionHandler.c         |  3 --
 MdePkg/Include/Library/DebugLib.h             | 40 ++++++++++++++++---
 MdePkg/Include/Library/PerformanceLib.h       | 12 +++++-
 3 files changed, 44 insertions(+), 11 deletions(-)

diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
index a39896d576..1d3ea61311 100644
--- a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
+++ b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
@@ -157,7 +157,6 @@ DescribeExceptionSyndrome (
   DEBUG ((DEBUG_ERROR, "\n %a \n", Message));
 }
 
-#ifndef MDEPKG_NDEBUG
 STATIC
 CONST CHAR8 *
 BaseName (
@@ -177,8 +176,6 @@ BaseName (
   return Str;
 }
 
-#endif
-
 /**
   This is the default action to take on an unexpected exception
 
diff --git a/MdePkg/Include/Library/DebugLib.h b/MdePkg/Include/Library/DebugLib.h
index 0db3b78ec8..4c073825c2 100644
--- a/MdePkg/Include/Library/DebugLib.h
+++ b/MdePkg/Include/Library/DebugLib.h
@@ -403,7 +403,12 @@ UnitTestDebugAssert (
       }                             \
     } while (FALSE)
 #else
-#define ASSERT(Expression)
+#define ASSERT(Expression)       \
+    do {                           \
+      if (FALSE) {                 \
+        (VOID) (Expression);       \
+      }                            \
+    } while (FALSE)
 #endif
 
 /**
@@ -426,7 +431,12 @@ UnitTestDebugAssert (
       }                            \
     } while (FALSE)
 #else
-#define DEBUG(Expression)
+#define DEBUG(Expression)        \
+    do {                           \
+      if (FALSE) {                 \
+        _DEBUG (Expression);       \
+      }                            \
+    } while (FALSE)
 #endif
 
 /**
@@ -452,7 +462,12 @@ UnitTestDebugAssert (
       }                                                                                  \
     } while (FALSE)
 #else
-#define ASSERT_EFI_ERROR(StatusParameter)
+#define ASSERT_EFI_ERROR(StatusParameter)                                             \
+    do {                                                                                \
+      if (FALSE) {                                                                      \
+        (VOID) (StatusParameter);                                                       \
+      }                                                                                 \
+    } while (FALSE)
 #endif
 
 /**
@@ -479,7 +494,12 @@ UnitTestDebugAssert (
       }                                                                 \
     } while (FALSE)
 #else
-#define ASSERT_RETURN_ERROR(StatusParameter)
+#define ASSERT_RETURN_ERROR(StatusParameter)                          \
+    do {                                                                \
+      if (FALSE) {                                                      \
+        (VOID) (StatusParameter);                                       \
+      }                                                                 \
+    } while (FALSE)
 #endif
 
 /**
@@ -534,7 +554,12 @@ UnitTestDebugAssert (
   are not included in a module.
 
 **/
-#define DEBUG_CODE_BEGIN()  do { if (DebugCodeEnabled ()) { UINT8  __DebugCodeLocal
+#define DEBUG_CODE_BEGIN()      \
+  do {                          \
+    BOOLEAN  __DebugCodeLocal;  \
+    __DebugCodeLocal = FALSE;   \
+    do {                        \
+      if (DebugCodeEnabled ()) {
 
 /**
   The macro that marks the end of debug source code.
@@ -545,7 +570,10 @@ UnitTestDebugAssert (
   are not included in a module.
 
 **/
-#define DEBUG_CODE_END()  __DebugCodeLocal = 0; __DebugCodeLocal++; } } while (FALSE)
+#define DEBUG_CODE_END()         \
+      }                          \
+    } while (__DebugCodeLocal);  \
+  } while (FALSE)
 
 /**
   The macro that declares a section of debug source code.
diff --git a/MdePkg/Include/Library/PerformanceLib.h b/MdePkg/Include/Library/PerformanceLib.h
index d0f2dfb070..57ba45eb7b 100644
--- a/MdePkg/Include/Library/PerformanceLib.h
+++ b/MdePkg/Include/Library/PerformanceLib.h
@@ -734,7 +734,12 @@ LogPerformanceMeasurement (
   Otherwise, the source lines between PERF_CODE_BEGIN() and PERF_CODE_END() are not included in a module.
 
 **/
-#define PERF_CODE_BEGIN()  do { if (PerformanceMeasurementEnabled ()) { UINT8  __PerformanceCodeLocal
+#define PERF_CODE_BEGIN()            \
+  do {                               \
+    BOOLEAN  __PerformanceCodeLocal; \
+    __PerformanceCodeLocal = FALSE;  \
+    do {                             \
+      if (PerformanceMeasurementEnabled ()) {
 
 /**
   Macro that marks the end of performance measurement source code.
@@ -744,7 +749,10 @@ LogPerformanceMeasurement (
   Otherwise, the source lines between PERF_CODE_BEGIN() and PERF_CODE_END() are not included in a module.
 
 **/
-#define PERF_CODE_END()  __PerformanceCodeLocal = 0; __PerformanceCodeLocal++; } } while (FALSE)
+#define PERF_CODE_END()                \
+      }                                \
+    } while (__PerformanceCodeLocal);  \
+  } while (FALSE)
 
 /**
   Macro that declares a section of performance measurement source code.