MySQL Bugs: #18815: libmysql using yassl can't be linked with c program

Bug #18815	libmysql using yassl can't be linked with c program
Submitted:	5 Apr 2006 15:38	Modified:	27 Apr 2006 20:16
Reporter:	Magnus Blåudd	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Compiling	Severity:	S2 (Serious)
Version:	5.0.21	OS:	Solaris (Solaris)
Assigned to:	Magnus Blåudd	CPU Architecture:	Any

Description:
It's not possible to link with libmysql from a c program if it includes yassl. You will get undefined symbols when linking.

These are for example Crun::pure_error which seems to be a function installed in the vtable of a class with pure virtual functions.

Workaround would be to include libCrun.so in the link.

Other symbols missing are "vector_des" and "vector_con" which might be related to "array delete". There is also the "register_exit_code" function.

How to repeat:
Look at the build status pages:

11629: cd /export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc
11630: CC=cc-5.0 CXX=CC ASFLAGS="-xarch=v8" CFLAGS="-xO3 -Xa -xstrconst -mt -D_FORTEC_ -xarch=v8 -xc99=none" CXXFLAGS="-xO3 -noex -mt -D_FORTEC_ -xarch=v8" LDFLAGS=-xarch=v8 LIBS=-lmtmalloc  perl /export/home/mysqldev/sol10-sparc-a/Do-mysqlclient-test
11631: 
11632: ##############################################################################
11633: #  Running Do-mysqlclient-test
11634: ##############################################################################
11635: 
11636: CC=cc-5.0
11637: CXX=CC
11638: CFLAGS=-I/export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/include -xO3 -mt -D_FORTEC_ -xarch=v8
11639: LIBS=-xarch=v8 -L/export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/lib -lmysqlclient -lz -lposix4 -lcrypt -lgen -lsocket -lnsl -lm
11640: 
11641: Running: cc-5.0  -I/export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/include -xO3 -mt -D_FORTEC_ -xarch=v8 test.c -xarch=v8 -L/export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/lib -lmysqlclient -lz -lposix4 -lcrypt -lgen -lsocket -lnsl -lm
11642: 
11643: Testing from C to link with all functions in libmysqlclient... Undefined			first referenced
11644:  symbol  			    in file
11645: __1cG__CrunKpure_error6F_v_         /export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/lib/libmysqlclient.a(libtaocrypt_la-asn.o)
11646: __1cG__CrunKvector_des6FpvIIpF1_v_v_ /export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/lib/libmysqlclient.a(libtaocrypt_la-algebra.o)
11647: __1cG__CrunKvector_con6FpvIIpF1_vp2_v_ /export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/lib/libmysqlclient.a(libtaocrypt_la-algebra.o)
11648: __1cG__CrunSregister_exit_code6FpG_v_v_ /export/home/mysqldev/sol10-sparc-a/test/mysql-standard-5.0.20-solaris10-sparc/lib/libmysqlclient.a(yassl_int.o)
11649: ld: fatal: Symbol referencing errors. No output written to a.out
11650: fail

Suggested fix:
For gcc compilers we have defined a __cxa_pure_virtual function and we need to do something similar here.

The pure_error symbol is inserted for classes with pure virtal functions. Ifthe pure part is removed from all classes in a file, the problem will go away(or move to another file...)

The register_exit_code symbol comes from declarations of singletons that are declared as a static const variable of a class.

Example:
yassl_int.hpp
class sslFactory {
   < snip>
private:
    static sslFactory instance_;
}

Later in yassl_int.cpp
Sessions Sessions::instance_; // simple singleton

The vector_des and vector_con calls are generated in the function AbstractEuclideanDomain::Gcd when arrays of objects are created on the stack.

const Integer& AbstractEuclideanDomain::Gcd(const Element &a,
                                            const Element &b) const
{
    Element g[3]={b, a};
    unsigned int i0=0, i1=1, i2=2;

    while (!Equal(g[i1], this->Identity()))
    {
        g[i2] = Mod(g[i0], g[i1]);
        unsigned int t = i0; i0 = i1; i1 = i2; i2 = t;
    }

    return result = g[i0];
}

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/4846

Patch has been sent for inclusion in upstream yaSSL.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/5072