Function evaluate_rule

src/engine/compile.cpp:58–161

 */

LIST * evaluate_rule( RULE * rule, OBJECT * rulename, FRAME * frame )
{
    LIST          * result = L0;
    profile_frame   prof[ 1 ];
    module_t      * prev_module = frame->module;

    if ( DEBUG_COMPILE )
    {
        /* Try hard to indicate in which module the rule is going to execute. */
        char buf[ 256 ] = "";
        if ( rule->module->name )
        {
            strncat( buf, object_str( rule->module->name ), sizeof( buf ) -
                1 );
            strncat( buf, ".", sizeof( buf ) - 1 );
            if ( strncmp( buf, object_str( rule->name ), strlen( buf ) ) == 0 )
            {
                buf[ 0 ] = 0;
            }
        }
        strncat( buf, object_str( rule->name ), sizeof( buf ) - 1 );
        debug_compile( 1, buf, frame );

        lol_print( frame->args );
        out_printf( "\n" );
    }

    if ( rule->procedure && rule->module != prev_module )
    {
        /* Propagate current module to nested rule invocations. */
        frame->module = rule->module;
    }

    /* Record current rule name in frame. */
    if ( rule->procedure )
    {
        frame->rulename = object_str( rulename );
        /* And enter record profile info. */
        if ( DEBUG_PROFILE )
            profile_enter( function_rulename( rule->procedure ), prof );
    }

    /* Check traditional targets $(<) and sources $(>). */
    if ( !rule->actions && !rule->procedure )
        unknown_rule( frame, NULL, frame->module, rulename );

    /* If this rule will be executed for updating the targets then construct the
     * action for make().
     */
    if ( rule->actions )
    {
        TARGETS * t;

        /* The action is associated with this instance of this rule. */
        ACTION * const action = (ACTION *)BJAM_MALLOC( sizeof( ACTION ) );
        memset( (char *)action, '\0', sizeof( *action ) );

        action->rule = rule;