diff --git a/Makefile b/Makefile
index 23f3222310..f50632ab74 100644
--- a/Makefile
+++ b/Makefile
@@ -113,7 +113,7 @@ ifneq ($(V),1)
    Q := @
 endif
 
-CFLAGS = -Wall -O3 -g -std=gnu99 -I.
+CFLAGS += -Wall -O3 -g -std=gnu99 -I.
 
 all: $(TARGET) config.mk
 
diff --git a/qb/qb.libs.sh b/qb/qb.libs.sh
index 579c91a44d..d73cec51cd 100644
--- a/qb/qb.libs.sh
+++ b/qb/qb.libs.sh
@@ -50,7 +50,7 @@ check_lib()
 
    extralibs="$4"
 
-   $CC -o $TEMP_EXE $TEMP_C $INCLUDE_DIRS $LIBRARY_DIRS $extralibs $2 2>/dev/null >/dev/null && answer=yes && eval HAVE_$1=yes
+   $CC -o $TEMP_EXE $TEMP_C $INCLUDE_DIRS $LIBRARY_DIRS $CFLAGS $LDFLAGS $extralibs $2 2>/dev/null >/dev/null && answer=yes && eval HAVE_$1=yes
 
    echo $answer
 
@@ -75,7 +75,7 @@ check_lib_cxx()
 
    extralibs="$4"
 
-   $CXX -o $TEMP_EXE $TEMP_CXX $INCLUDE_DIRS $LIBRARY_DIRS $extralibs $2 2>/dev/null >/dev/null && answer=yes && eval HAVE_$1=yes
+   $CXX -o $TEMP_EXE $TEMP_CXX $INCLUDE_DIRS $LIBRARY_DIRS $CFLAGS $LDFLAGS $extralibs $2 2>/dev/null >/dev/null && answer=yes && eval HAVE_$1=yes
 
    echo $answer