Glibc warning concerning use of getaddrinfo() in static library

dwhitney67 · 06-19-2009, 07:43 AM

I am using a static library in which one of the modules employs the use of getaddrinfo().

When I link the library with an application, I get the following warning:

Code:

libSocket++.a(SocketUtility.o): In function `socketpp::FillAddress(int, char const*, unsigned short, sockaddr_in*)':
/home/whitneyd/Redirector/SocketLibrary-1.1.6/socket++/SocketUtility.cpp:114: warning: Using 'getaddrinfo' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking

Is there any way to prevent this warning from occurring? I've tried linking the static version of the C library (/usr/lib/libc.a, by specifying "-static -lc" as one of my linker options, but that did not work.

Here is the Makefile I am using:

Code:

APP      = udp_redir

SRCS     = udp_redir.cpp
OBJS     = $(SRCS:.cpp=.o)

CXXFLAGS = -Wall -pedantic -ansi
INCLUDES = -I./include
LDFLAGS  = -L./lib
LIBS     = -static -lSocket++ -static -lc 

all: SocketLibrary $(APP)

$(APP): $(OBJS)
        @echo Linking $@
        @$(CXX) $^ $(LDFLAGS) $(LIBS) -o $@

.cpp.o:
        @echo Compiling $<
        @$(CXX) $(CXXFLAGS) $(INCLUDES) -c $<

clean:
        @make -s -C SocketLibrary* DEST=.. clean
        $(RM) $(OBJS)

distclean: clean
        @make -s -C SocketLibrary* DEST=.. distclean
        @$(RM) -r SocketLibrary*
        @$(RM) ./.getLib
        @$(RM) -r include lib
        $(RM) $(APP)

SocketLibrary: .getLib
        @echo Building SocketLibrary
        @make -s -C SocketLibrary* DEST=.. install

.getLib:
        @$(RM) -r SocketLibrary*
        @wget http://softhouseproductions.com/SocketLibrary.tgz >& /dev/null
        @tar xzf SocketLibrary.tgz
        @$(RM) SocketLibrary.tgz
        @touch $@

gnashley · 06-19-2009, 01:28 PM

I think you posted about this elsewhere... the answer is that some glibc functions simply cannot be linked statically and still work. IF you want to use those functions you need to supply or depend on the shared libraries being present at runtime, or use some other libc to link against -I'm not sure, though, if newlib or uClibc will let you do this either.

dwhitney67 · 06-19-2009, 01:38 PM

If I had posted this topic before, I must have been inebriated, because I do not recall doing such.

Anyhow, I understand the cause of the warning, and your answer seems to confirm that. I was just wondering if there was a way to remove the warning, perhaps by statically linking the C library into the app. But it does not appear as if this is possible, nor when I think about it, be very practical.

Fortunately for me, I only use the SocketLibrary on Linux distros, so portability to other OSes is not a concern.

Thanxs for your reply.

gnashley · 06-19-2009, 01:43 PM

Sorry, I must be mistaken -but I just saw a posting yesterday about the same fucntion plus a couple of others.
If you are statically linking, it would be worth checking out newlib and/or uclibc as using them will provide much smaller binaries. uClibc, especially, claims to be better for staically-linking. newlib is less feature-full.