Hi Mike, What you suggested does work for MSVC, but it is failing with GCC. It sems that GCC is very strict about operator names. Relevant errors below: error: "xor" cannot be used as a macro name as it is an operator in C++ #define xor XOR ^~~ error: "xor" cannot be used as a macro name as it is an operator in C++ #undef xor MdePkg/Include/IndustryStandard/Tpm20.h:1250:21: error: expected unqualified-id before 'xor' token TPMI_ALG_HASH xor; ^~~ MdePkg/Include/IndustryStandard/Tpm20.h:1323:20: error: expected unqualified-id before 'xor' token TPMS_SCHEME_XOR xor; ^~~ Aaron From: Kinney, Michael D Sent: Wednesday, May 24, 2023 12:49 PM To: Aaron Pop ; devel@edk2.groups.io Cc: Kinney, Michael D Subject: [EXTERNAL] RE: GoogleTest Compatibility with MdePkg's IndustyStandard header files Hi Aaron, Don't know if this will completely resolve your issues, but if you add some preprocessor statements around the problematic includes in your unit test CPP file, you may be able to get it to build. For example, I added the highlighted lines to MdePkg\Test\GoogleTest\Library\BaseSafeIntLib\TestBaseSafeIntLib.cpp and I can get that unit test to build. Without the #define/#undef lines it fails in the way you describe. #include extern "C" { #include #include #define operator operator_ #define xor xor_ #include #include #undef operator #undef xor } Mike From: Aaron Pop > Sent: Monday, May 22, 2023 5:41 PM To: devel@edk2.groups.io Cc: Kinney, Michael D > Subject: GoogleTest Compatibility with MdePkg's IndustyStandard header files Google Test, and CPP, has more keywords C uses. Tpm12.h and Tpm20.h have references to struct names that are `operator` and `xor`, both of which trigger build errors because they conflict with CPP's keywords. Operator triggered a build error in MSVC. Xor only triggered a build error under GCC, MSVC did not have a problem with it. The work arounds suggested in the call, (using defines to get around the conflict) worked for operator, but did not work for xor with gcc. Tpm12.h: TPM_PERMANENT_FLAGS BOOLEAN operator; Tpm20.h: TPMU_SCHEME_KEYEDHASH TPMS_SCHEME_XOR xor; TPMU_SYM_KEY_BITS TPMI_ALG_HASH xor; What is the suggested method of trying to make existing header files compatible with google test? Thanks, Aaron