ENGINE-864: option -fvisibility=hidden is viral, so add it here, too.

src/Makefile

@@ -4,7 +4,7 @@
 .PHONY: lib all clean install test
 
 CXX=c++
-CXXFLAGS+=-Wall -O0 -std=c++14 -g -fPIC -fstack-protector-all -DLOG_TO_STDERR -fsanitize=address
+CXXFLAGS+=-Wall -O0 -std=c++14 -g -fPIC -fstack-protector-all -DLOG_TO_STDERR -fsanitize=address -fvisibility=hidden
 LDFLAGS+=-fsanitize=address
 
 PREFIX=/usr/local
@@ -36,10 +36,10 @@ else ifeq ($(BUILD_FOR),Darwin)
     TARGET=libpEpMIME.dylib
 endif
 
-lib: libpEpMIME.a
-
 all: libpEpMIME.a unittests fuzz $(TARGET)
 
+lib: libpEpMIME.a
+
 -include local.conf
 
 LIB_OBJ=pEpMIME.o pEpMIME_internal.o rules.o bodyparser.o \
@@ -90,7 +90,7 @@ clean:
 		*.a \
 		unittests fuzz $(TARGET)
 
-install: lib
+install: lib $(TARGET)
 	mkdir -p $(PREFIX)/include/pEp
 	cp -v pEpMIME.hh $(PREFIX)/include/pEp
 	mkdir -p $(PREFIX)/lib