try fixing macos gcc builds 7

_build.sh

@@ -916,25 +916,27 @@ build_single_target() {
   _CFLAGS_GLOBAL+=' -fno-omit-frame-pointer'
   _CXXFLAGS_GLOBAL+=' -fno-omit-frame-pointer'
 
-  # https://fedoraproject.org/wiki/Security_Features_Matrix
-  # RISC-V: https://gcc.gnu.org/onlinedocs/gcc/RISC-V-Options.html
-  if [ "${_CPU}" = 'x64' ] || \
-     [ "${_CPU}" = 'x86' ]; then
-    # https://maskray.me/blog/2022-12-18-control-flow-integrity
-    _CFLAGS_GLOBAL+=' -fcf-protection=full'
-    _CXXFLAGS_GLOBAL+=' -fcf-protection=full'
-    if [ "${_OS}" = 'linux' ]; then
-      # https://github.com/llvm/llvm-project/issues/44828
-      # https://reviews.llvm.org/D59780
-      # https://github.com/llvm/llvm-project/commit/7cd429f27d4886bb841ed0e3702e970f5f6cccd1
-      _LDFLAGS_GLOBAL+=' -Wl,-z,cet-report=warning -Wl,-z,force-ibt,-z,shstk'
-    elif [ "${_OS}" = 'win' ] && [ "${_CC}" = 'llvm' ]; then
-      _LDFLAGS_GLOBAL+=' -Wl,-Xlink=-cetcompat'
+  if [ "${_OS}" != 'mac' ] || [ "${_CC}" != 'gcc' ]; then  # skip for mac-gcc
+    # https://fedoraproject.org/wiki/Security_Features_Matrix
+    # RISC-V: https://gcc.gnu.org/onlinedocs/gcc/RISC-V-Options.html
+    if [ "${_CPU}" = 'x64' ] || \
+       [ "${_CPU}" = 'x86' ]; then
+      # https://maskray.me/blog/2022-12-18-control-flow-integrity
+      _CFLAGS_GLOBAL+=' -fcf-protection=full'
+      _CXXFLAGS_GLOBAL+=' -fcf-protection=full'
+      if [ "${_OS}" = 'linux' ]; then
+        # https://github.com/llvm/llvm-project/issues/44828
+        # https://reviews.llvm.org/D59780
+        # https://github.com/llvm/llvm-project/commit/7cd429f27d4886bb841ed0e3702e970f5f6cccd1
+        _LDFLAGS_GLOBAL+=' -Wl,-z,cet-report=warning -Wl,-z,force-ibt,-z,shstk'
+      elif [ "${_OS}" = 'win' ] && [ "${_CC}" = 'llvm' ]; then
+        _LDFLAGS_GLOBAL+=' -Wl,-Xlink=-cetcompat'
+      fi
+    elif [ "${_CPU}" = 'a64' ]; then
+      # https://gcc.gnu.org/onlinedocs/gcc/AArch64-Options.html
+      _CFLAGS_GLOBAL+=' -mbranch-protection=standard'
+      _CXXFLAGS_GLOBAL+=' -mbranch-protection=standard'
     fi
-  elif [ "${_CPU}" = 'a64' ]; then
-    # https://gcc.gnu.org/onlinedocs/gcc/AArch64-Options.html
-    _CFLAGS_GLOBAL+=' -mbranch-protection=standard'
-    _CXXFLAGS_GLOBAL+=' -mbranch-protection=standard'
   fi
 
   _CMAKE_GLOBAL+=' -DCMAKE_INSTALL_MESSAGE=NEVER'