fix: undef _FORTIFY_SOURCE before setting

.github/workflows/ci.yml

@@ -40,14 +40,6 @@ jobs:
           - os: "windows-2022"
             compiler: "msvc"
             vcvarsall: false
-          - os: "macos-11"
-            compiler: "gcc"
-            cmake: true
-            vcvarsall: true
-          - os: "macos-13"
-            compiler: "gcc"
-            cmake: true
-            vcvarsall: true
         exclude:
           # fails with an internal error
           - os: "macos-12"

src/Hardening.cmake

@@ -44,7 +44,7 @@ function(
         list(APPEND HARDENING_COMPILE_OPTIONS -Wstringop-overflow=4 -Wformat-overflow=2)
       endif()
 
-      target_compile_definitions(${_project_name} INTERFACE $<$<CONFIG:Release,RelWithDebInfo>:_FORTIFY_SOURCE=3>)
+      target_compile_options(${_project_name} INTERFACE $<$<CONFIG:Release,RelWithDebInfo>:-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3>)
     endif()
 
     if(${ENABLE_ELF_PROTECTION})

tests/myproj/CMakeLists.txt

@@ -88,6 +88,10 @@ project_options(
   # CLANG_WARNINGS "-Weverything"
   LINKER
   "${LINKER}"
+
+  # Test if _FORTIFY_SOURCE is defined only once when ENABLE_OVERFLOW_PROTECTION
+  ENABLE_OVERFLOW_PROTECTION
+  CLANG_TIDY_EXTRA_ARGUMENTS "-warnings-as-errors=clang-diagnostic-macro-redefined"
 )
 # NOTE: project_options and project_warnings are defined inside project_options