Remove internal data zero initialization

Description

Specify whether to generate initialization code for internal work structures, such as block states and block outputs, to zero.

Category: Optimization

Settings

Default: When you set the Code interface packaging parameter to Nonreusable function, the Remove internal data zero initialization check box is selected. At the command line, ZeroInternalMemoryAtStartup is set to 'off'. When you set the Code interface packaging parameter to Reusable function or C++ Class, the Remove internal data zero initialization check box is cleared and ZeroInternalMemoryAtStartup is set to 'on'.

On

Does not generate code that initializes internal work structures to zero.

During startup, standards-compliant C and C++ compilers initialize global data to zero, eliminating the need to include zero initialization code for this data in the generated code. Standards-compliant compilers do not necessarily initialize dynamically allocated data and local variables to zero. Before leaving the Remove internal data zero initialization parameter selected, confirm that your model meets these conditions:

If your compiler is not standards-compliant, confirm that it initializes global data to zero.
If you set the Code Interface packaging to Reusable function or C++ class, confirm that data is either statically allocated or that dynamically allocated data is initialized to zero.

Generated code initializes data that you specify in an Initialize Function block, even if you select this parameter.

Off

Generates code that initializes internal work structures to zero.

Generated code does not initialize data whose storage class has imported scope, unless you specify that data in an Initialize Function block.

The Remove internal data zero initialization check box is cleared. ZeroInternalMemoryAtStartup is set to 'on' and is read-only for a model in which the Code interface packaging parameter is set to C++ class and you have selected the Use dynamic memory allocation for model initialization parameter.

If you set the Code interface packaging parameter to Reusable function and select the Use dynamic memory allocation for model block instantiation parameter, the Remove internal data zero initialization check box is cleared and ZeroInternalMemoryAtStartup is set to 'on'.

Dependencies

This parameter appears only for ERT-based targets.
This parameter requires Embedded Coder^® when generating code.

Command-Line Information

Parameter: ZeroInternalMemoryAtStartup

Value: 'off' | 'on'

Default: 'off'

Note

The command-line values are the reverse of the settings values. At the command line, 'on' corresponds to the description of “Off” in the settings section. 'off' corresponds to the description of “On” in the settings section.

Recommended Settings

Application	Setting
Debugging	No impact
Traceability	No impact
Efficiency	On (GUI), `off` (command line), (execution, ROM), No impact (RAM)
Safety precaution	No recommendation