diff --git a/Dockerfile b/Dockerfile
index 8779fee570..0c4556cadf 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -55,9 +55,9 @@ RUN cd /afl-cov && make install && cd ..
 COPY . /AFLplusplus
 WORKDIR /AFLplusplus
 
-RUN export REAL_CXX=g++-10 && export CC=gcc-10 && \
+RUN export export CC=gcc-10 && \
     export CXX=g++-10 && make clean && \
-    make distrib CFLAGS="-O3 -funroll-loops -D_FORTIFY_SOURCE=2" && make install && make clean
+    make distrib && make install && make clean
 
 RUN echo 'alias joe="jupp --wordwrap"' >> ~/.bashrc
 RUN echo 'export PS1="[afl++]$PS1"' >> ~/.bashrc
diff --git a/GNUmakefile b/GNUmakefile
index 4ba5d3b317..45fa3ba18c 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -77,17 +77,17 @@ ifeq "$(shell echo 'int main() {return 0; }' | $(CC) -fno-move-loop-invariants -
 	SPECIAL_PERFORMANCE += -fno-move-loop-invariants -fdisable-tree-cunrolli
 endif
 
-ifeq "$(shell echo 'int main() {return 0; }' | $(CC) $(CFLAGS) -Werror -x c - -march=native -o .test 2>/dev/null && echo 1 || echo 0 ; rm -f .test )" "1"
-  ifndef SOURCE_DATE_EPOCH
-    HAVE_MARCHNATIVE = 1
-    CFLAGS_OPT += -march=native
-  endif
-endif
+#ifeq "$(shell echo 'int main() {return 0; }' | $(CC) $(CFLAGS) -Werror -x c - -march=native -o .test 2>/dev/null && echo 1 || echo 0 ; rm -f .test )" "1"
+#  ifndef SOURCE_DATE_EPOCH
+#    HAVE_MARCHNATIVE = 1
+#    CFLAGS_OPT += -march=native
+#  endif
+#endif
 
 ifneq "$(shell uname)" "Darwin"
-  ifeq "$(HAVE_MARCHNATIVE)" "1"
-    SPECIAL_PERFORMANCE += -march=native
-  endif
+  #ifeq "$(HAVE_MARCHNATIVE)" "1"
+  #  SPECIAL_PERFORMANCE += -march=native
+  #endif
  # OS X does not like _FORTIFY_SOURCE=2
   ifndef DEBUG
     CFLAGS_OPT += -D_FORTIFY_SOURCE=2
diff --git a/qemu_mode/qemuafl b/qemu_mode/qemuafl
index 246c1777f4..9a258d5b7a 160000
--- a/qemu_mode/qemuafl
+++ b/qemu_mode/qemuafl
@@ -1 +1 @@
-Subproject commit 246c1777f453a280cbafc57f92742147ffc72818
+Subproject commit 9a258d5b7a38c045a6e385fcfcf80a746a60e557