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CS107 Assignment file couldn't compile, missing expat.h and thread_107.h files


I was auditing cs107 at stanford online

The problem I ran into is with assignment 6, when I type "make" in terminal, the error message pops up. Basically, I miss two header files, which I guess can be got from the pre-compiled .lib file. But somehow it just doesn't work.

Here's part of the original make file:

CFLAGS = -D_REENTRANT -g -Wall -D__ostype_is_$(OSTYPE)__ -std=gnu99 -I/usr/class/cs107/include/ -Wno-unused-function $(DFLAG)
LDFLAGS = -L/usr/class/cs107/assignments/assn-6-rss-news-search-lib/$(OSTYPE) -L/usr/class/cs107/lib -lexpat -lrssnews $(PLATFORM_LIBS) $(THREAD_LIBS)
PFLAGS= -linker=/usr/pubsw/bin/ld -best-effort -threads=yes -max-threads=1000

Edit:

When I said "This is supposed to compile even without threading implementation", I meant that it should compile without FURTHER threading implementation by students.

So here's the error message with thread:

gcc -D_REENTRANT -g -Wall -D__ostype_is_linux__ -std=gnu99 -I/usr/class/cs107/include/ -Wno-unused-function -c -o rss-news-search.o rss-news-search.c
rss-news-search.c: In function ‘main’:
rss-news-search.c:109:3: warning: implicit declaration of function ‘InitThreadPackage’ [-Wimplicit-function-declaration]
gcc rss-news-search.o -D_REENTRANT -g -Wall -D__ostype_is_linux__ -std=gnu99 -I/usr/class/cs107/include/ -Wno-unused-function -L/home/h/cs107/assn-6-rss-news-search-lib/linux -L/usr/class/cs107/lib -L. -lexpat -lrssnews -lnsl -lpthread -lthread_107_linux -o rss-news-search
/usr/bin/ld: cannot find -lthread_107_linux
collect2: ld returned 1 exit status
make: *** [rss-news-search] Error 1

here's the error message without $(THREAD_LIBS):

gcc -D_REENTRANT -g -Wall -D__ostype_is_linux__ -std=gnu99 -I/usr/class/cs107/include/ -Wno-unused-function -c -o rss-news-search.o rss-news-search.c
rss-news-search.c: In function ‘main’:
rss-news-search.c:109:3: warning: implicit declaration of function ‘InitThreadPackage’ [-Wimplicit-function-declaration]
gcc rss-news-search.o -D_REENTRANT -g -Wall -D__ostype_is_linux__ -std=gnu99 -I/usr/class/cs107/include/ -Wno-unused-function -L/home/h/cs107/assn-6-rss-news-search-lib/linux -L/usr/class/cs107/lib -L. -lexpat -lrssnews -lnsl -lpthread  -o rss-news-search
rss-news-search.o: In function `main':
/home/h/cs107/assn-6-rss-news-search/rss-news-search.c:109: undefined reference to `InitThreadPackage'
collect2: ld returned 1 exit status
make: *** [rss-news-search] Error 1

In the later case, if I comment out "InitThreadPackage", it compiles just fine.


Solution

  • This is the procedure to compile your project:

    1. Create a file assn-6-rss-news-search/thread_107.h, and put this inside:

      /* Empty header file */

    2. Copy the library librssnews.a from assn-6-rss-news-search-lib/linux/ to assn-6-rss-news-search/

    3. Modify the file rss-news-search.c by commenting the call to the function : InitThreadPackage on line 109:

      //InitThreadPackage(false);

    4. Modify the Makefile to include the path to the current directory (to be able to link to the library you've copied earlier librssnews.a):

    The line 27 should look like this:

    LDFLAGS = -L/usr/class/cs107/assignments/assn-6-rss-news-search-lib/$(OSTYPE) -L/usr/class/cs107/lib -L. -lexpat -lrssnews $(PLATFORM_LIBS) $(THREAD_LIBS)
    

    Then:

    make clean
    make
    

    EDIT :

    When you got this error cannot find lthread_107_linux, Edit your Makefile to remove this $(THREAD_LIBS) on line 27:

    LDFLAGS = -L/usr/class/cs107/assignments/assn-6-rss-news-search-lib/$(OSTYPE) -L/usr/class/cs107/lib -L. -lexpat -lrssnews $(PLATFORM_LIBS)