Add comments about the missing $CFGUARD_ARGS when building sanitizers

Dockerfile.dev

@@ -132,6 +132,7 @@ RUN cd test && \
 
 # Build sanitizers. Ubsan includes <typeinfo> from the C++ headers, so
 # we need to build this after libcxx.
+# $CFGUARD_ARGS is intentionally omitted here.
 RUN ./build-compiler-rt.sh $TOOLCHAIN_PREFIX --build-sanitizers
 
 # Sanitizers on windows only support x86.

build-all.sh

@@ -89,6 +89,6 @@ fi
 ./build-compiler-rt.sh $PREFIX $CFGUARD_ARGS
 ./build-libcxx.sh $PREFIX $CFGUARD_ARGS
 ./build-mingw-w64-libraries.sh $PREFIX $CFGUARD_ARGS
-./build-compiler-rt.sh $PREFIX --build-sanitizers
+./build-compiler-rt.sh $PREFIX --build-sanitizers # CFGUARD_ARGS intentionally omitted
 ./build-libssp.sh $PREFIX $CFGUARD_ARGS
 ./build-openmp.sh $PREFIX $CFGUARD_ARGS