未定义的引用`clock_gettime＆＃39;，即使在＆＃39; lrt＆＃39;在里面。图书馆问题？

Question

尝试在播放器/舞台中编译此文件，我不断收到未定义的错误。

CXX = g++
CFLAGS = -Wall -o2 -I /usr/local/include/player-2.1/ -lrt
DEBUGFLAGS = 
HEADERS = 
SOURCES = gossip.cc
OBJECTS = $(SOURCES:.cpp=.o)
PKG_LIBS = `pkg-config --libs playerc++`
EXE = gossip


all: $(SOURCES) $(HEADERS)
    $(CXX) $(CFLAGS) $(DEBUGFLAGS) -o $(EXE) `pkg-config--cflags playerc++` $(SOURCES) $(PKG_LIBS)

clean:
    rm -rf $(EXE) *.o

错误：

undefined reference to `clock_gettime'

么？