#216 Incorrect C code is generated if an unguarded transition appears before a guarded one

[Maksim Salau]

Hi,

SMC v6.6.3 generates invalid code (tested C and C++) if an unguarded transition is defined before a guarded one.

E.g.:

state
{
    event nil {}
    event [ isCond() ] state {}
}

gives the following C++ code:

:::C++
    void fsm_state::event(sampleContext& context)
    {


        else
        {
        }
        else if ( isCond() )

    {
            context.getState().Exit(context);
            // No actions.
            context.setState(fsm::state);
            context.getState().Entry(context);
        }

    }

or C code:

:::C++
static void pkg_fsm_state_event(struct pkg_sampleContext *const fsm)
{


    else {
    }
    else if ( isCond() ) {
        /* No actions. */
        setState(fsm, &pkg_fsm_state);
    }
}

Expected behaviour (to my mind) is either to generate correct code or to fail during code generation.

Changing order of transitions gives correct code.

state
{
    event [ isCond() ] state {}
    event nil {}
}

gives:

:::C++
    void fsm_state::event(sampleContext& context)
    {

        if ( isCond() )
        {
            context.getState().Exit(context);
            // No actions.
            context.setState(fsm::state);
            context.getState().Entry(context);
        }
        else
        {
        }

    }

or:

:::C++
static void pkg_fsm_state_event(struct pkg_sampleContext *const fsm)
{

    if ( isCond() ) {
        /* No actions. */
        setState(fsm, &pkg_fsm_state);
    }
    else {
    }
}

Please see the attached files:

• sample.sm - the minimalistic state machine description that reproduces the issue;
• sample_sm.c - generated C code (java -jar ./Smc.jar -c ./sample.sm);
• sample_sm.cpp - generated C++ code (java -jar ./Smc.jar -c++ ./sample.sm).

P.S.: SMC reports incorrect version.
Smc.jar from smc_6_6_3.tgz gives the following:

$ java -jar ./Smc.jar -version
smc v. 6.6.0

Also README.txt in the released tarball is outdated:

                               SMC
                     The State Machine Compiler
                         (Version: 6.6.2)

Thanks,
Maksim.

[Charles Rapp]

This is the case for the following target languages:

• C
• C++
• C#
• Groovy
• Java (-java & -java7
• Javascript
• Lua
• Objective-C
• Perl
• PHP
• Python
• Ruby
• Scala
• Tcl
• VB.net

[David Rea]

Can this be closed with the release of 7.1.0?

[Maksim Salau]

Hi David,

I've tested v7.1.0 and it works perfectly. Thanks!

Regards,
Maksim

[Charles Rapp]

Better late than never: this issue was indeed fixed in SMC release 7.1.0.