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Gcc Linker Error Undefined Reference


simplemain.o -lbar_dep -lfunc_dep ./libfunc_dep.a(func_dep.o): In function 'func': func_dep.c:(.text+0x14): undefined reference to 'bar' collect2: ld returned 1 exit status To solve this, consider that it's perfectly valid to list a library more are included 1 Linker error. It has always been thus, since the beginning of (Unix) time — some time in the 1970s, anyway. –Jonathan Leffler Nov 25 '13 at 1:42 It seems that the The symbols it imports: these are added to the list of undefined symbols, unless they can be found in the list of exported symbols. this contact form

I use this command: gcc -L/media/sf_BitEagle_Projects/cbitcoin/build/bin -lcbitcoin \ -Wl-rpath,/media/sf_BitEagle_Projects/cbitcoin/build/bin -lssl -lcrypto \ -L/usr/local/ssl/lib/ -o /media/sf_BitEagle_Projects/cbitcoin/build/bin/testCBAddress \ /media/sf_BitEagle_Projects/cbitcoin/build/obj/testCBAddress.o \ /media/sf_BitEagle_Projects/cbitcoin/build/obj/CBOpenSSLCrypto.o The bin directory is the location of the library. Any help would be appreciated. For example, circular dependency problems can be easily resolved with --start-group and --end-group. The typical UNIX linker works from left to right, so put all your dependent libraries on the left, and the ones that satisfy those dependencies on the right of the link http://stackoverflow.com/questions/12272864/linker-error-on-linux-undefined-reference-to

Gcc Linker Error Undefined Reference

It is not possible 0 Should the order of linked libraries make a difference in compilation? 0 what is compilation error with gcc 0 Linker Error when compiling with static library Book of zen kōans Developing web applications for long lifespan (20+ years) Make all the statements true Why do train companies require two hours to deliver your ticket to the machine? No Library To understand this issue, remember that a header file (.h) is not a library. share|improve this answer answered Sep 5 '08 at 3:56 titanae 1,60911526 add a comment| up vote 1 down vote Link order certainly does matter, at least on some platforms.

The reason for this is simple: even without us explicitly asking for it, gcc asks the linker to link the C library as well. Where are sudo's insults stored? True or False? Ld Undefined Reference To Function If so, how, etc.

Back to the original example Let's go back to the example this article started with. You need to precede each library in the group list with -Xlinker share|improve this answer edited Jan 11 '12 at 6:44 sra 21.4k63975 answered Aug 9 '11 at 8:06 yundorri 411 Conference presenting: stick to paper material? http://stackoverflow.com/questions/143530/linker-woes-undefined-reference For details and our forum data attribution, retention and privacy policy, see here Skip to content Follow: RSS Twitter Late Developer Random thoughts of an old C++ guy Home About Me

Unsubstantiated How does NumPy solve least squares for underdetermined systems? Linking Undefined Reference To But I would like to have an easy to use LD commandline option with those methods you mention too. In your source file myapp.c you include the header, either directly or including another header that includes it. Linked 4 OpenCV undefined references 4 Unable to link to libgfortran.a 0 Undefined reference to PQfinish even though libraries etc.

Undefined Reference To Function In Shared Library

I have included the headers directory using -I and i'm sure it's being found. Do you want to help us debug the posting issues ? < is the place to report it, thanks ! Gcc Linker Error Undefined Reference But AA can't come both before and after BB on the command-line, right? Gcc Linking Order Let's compile it and look at the symbol table: $ gcc -c x.c $ nm x.o 000000000000000e T exported U imported 0000000000000000 t internal This means: exported is an external symbol

more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed weblink Only a library resolves the symbol, it takes the object files of that library to resolve the symbol (b.o out of libb.a in this case). I have installed gcc on a NSLU2. The linker then searches those enclosed lib multiple times to ensure cycling dependencies are resolved. Gcc Undefined Reference To Function

In it, you'll get: The week's top questions and answers Important community announcements Questions that need answers see an example newsletter By subscribing, you agree to the privacy policy and terms Reply With Quote 06-24-2014 #9 b2rdark View Profile View Forum Posts Private Message View Articles Just Joined! share|improve this answer answered Mar 21 '10 at 16:08 David Wheeler 95163 7 +1 Oh, thank you! navigate here But obviously I am missing something fundamental.

So change to this: Code: test: test.o ${CC} ${CFLAGS} -o [email protected] $^ ${LDFLAGS} and it should work. Undefined Reference Gcc Is there any way to know when NOT to use my Oyster card? Results 1 to 4 of 4 Thread: compiling with gcc and "undefined reference to xxx" Thread Tools Show Printable Version Subscribe to this Thread… Display Linear Mode Switch to Hybrid Mode

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I have found this solution at https://gcc.gnu.org/gcc-5/porting_to.html share|improve this answer answered Oct 11 at 16:43 mvi 1 add a comment| Your Answer draft saved draft discarded Sign up or log And if you're not using a Makefile, well that's the problem. For more information, see Toolchain Transition in Natty Narwhal. Linker Error Undefined Reference To But sometimes there is no order, if you have cyclic references.

Putting pin(s) back into chain Can a GM prohibit a player from referencing spells in the handbook during combat? cov(x,y)=0 but corr(x,y)=1 Can I release a pattern without releasing the whole held expression? If not, it will create "/usr/lib/x86_64-linux-gnu/libpci.a" which might resolve the problem. his comment is here Now, suppose this is part of a larger project that consists of many object files and libraries, and somewhere within the project there's a library that contains this code: void memcpy(char*

But when I try to compile the file that I really want to use "vclient.c" I get an error message /tmp/ccuuPxtN.o(.text+0x3bc): In function `main': vclient.c: undefined reference to `initLog' Now as I'll try this when I'm next able to... –Matthew Mitchell Sep 5 '12 at 0:12 Yes, worked perfectly thank you. –Matthew Mitchell Sep 5 '12 at 20:23 3 imported is an undefined symbol; in other words, the linker is expected to find it elsewhere. To allow the linker find the function's implementation (and get rid of the undefined reference) you need to ask the compiler driver (gcc) to link the specific library where the function

Odd. internal is defined within the object but invisible from the outside. True it also has a script to figure out compile/link options - but you can't use that in all circumstances. –Steve314 Jul 11 '10 at 13:27 6 @Steve that's what Second, the discussion here resolves around static linking that's done at compile/link time.

I would add to the section on resolving cyclic dependencies, I'll leave it to the original poster if they wish to modify, that when passing the --start-group and --end-group options using All rights reserved. Crash? No .so files at all.

This code illustrates the problem: int foo(); int main() { foo(); } Here, we have a declaration of the function foo(), which we call in main(), but no definition. GCC version: gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3 On Linux Mint 13 Thank you. Join them; it only takes a minute: Sign up Trying to include a library, but keep getting 'undefined reference to' messages up vote 36 down vote favorite 18 I am attempting I know link resolve order makes perfect sense, but it really helps to be reminded of these facts! –scraimer Dec 20 '11 at 6:15 1 This worked for me.

Let's start with the most basic case, of linking two objects together: $ cat simplefunc.c int func(int i) { return i + 21; } $ cat simplemain.c int func(int); int main(int Suppose you have two C++ source files: // f1.cpp int foo(); int main() { foo(); } and: // f2.cpp int foo() { return 42; } If you compile f1.cpp on its