[PATCH 1/2] MdePkg: Update Base.h to be compliant with C11

["Rebecca Cran" <quic_rcran@quicinc.com>]

With the introduction of the use of _Static_assert, edk2 requires a C11
compatible compiler. Update Include/Base.h to be compliant with C11.

As of C11, the maximum type of an enum is type `int`. Since the UEFI
Specification 2.3.1 Errata C allows either `int` or `unsigned int`, fix
the 32-bit enum check to use a signed int.

Since the UEFI 2.3 Specification only allowed signed int, update the
comment to reference 2.3.1 Errata C where the change was made to allow
unsigned int.

Signed-off-by: Rebecca Cran <rebecca@quicinc.com>
---
 MdePkg/Include/Base.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/MdePkg/Include/Base.h b/MdePkg/Include/Base.h
index d209e6de280a..e89c84962ab2 100644
--- a/MdePkg/Include/Base.h
+++ b/MdePkg/Include/Base.h
@@ -796,9 +796,9 @@ STATIC_ASSERT (sizeof (L"A")    == 4, "sizeof (L\"A\") does not meet UEFI Specif
 //
 // The following three enum types are used to verify that the compiler
 // configuration for enum types is compliant with Section 2.3.1 of the
-// UEFI 2.3 Specification. These enum types and enum values are not
-// intended to be used. A prefix of '__' is used avoid conflicts with
-// other types.
+// UEFI 2.3.1 Errata C Specification. These enum types and enum values
+// are not intended to be used. A prefix of '__' is used avoid
+// conflicts with other types.
 //
 typedef enum {
   __VerifyUint8EnumValue = 0xff
@@ -809,12 +809,12 @@ typedef enum {
 } __VERIFY_UINT16_ENUM_SIZE;
 
 typedef enum {
-  __VerifyUint32EnumValue = 0xffffffff
-} __VERIFY_UINT32_ENUM_SIZE;
+  __VerifyInt32EnumValue = 0x7fffffff
+} __VERIFY_INT32_ENUM_SIZE;
 
 STATIC_ASSERT (sizeof (__VERIFY_UINT8_ENUM_SIZE) == 4, "Size of enum does not meet UEFI Specification Data Type requirements");
 STATIC_ASSERT (sizeof (__VERIFY_UINT16_ENUM_SIZE) == 4, "Size of enum does not meet UEFI Specification Data Type requirements");
-STATIC_ASSERT (sizeof (__VERIFY_UINT32_ENUM_SIZE) == 4, "Size of enum does not meet UEFI Specification Data Type requirements");
+STATIC_ASSERT (sizeof (__VERIFY_INT32_ENUM_SIZE) == 4, "Size of enum does not meet UEFI Specification Data Type requirements");
 
 /**
   Macro that returns a pointer to the data structure that contains a specified field of
-- 
2.30.2