runtime_checks
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The latest version of this topic can be found at runtime_checks. Disables or restores the /RTC settings.
Syntax
#pragma runtime_checks
( "[runtime_checks]", {restore | off} )
Remarks
You cannot enable a run-time check that was not enabled with a compiler option. For example, if you do not specify /RTCs, specifying #pragma runtime_checks( "s", restore) will not enable stack frame verification.
The runtime_checks pragma must appear outside a function and takes effect at the first function defined after the pragma is seen. The restore and off arguments turn options specified in the runtime_checks on or off.
The runtime_checks can be zero or more of the parameters shown in the following table.
Parameters of the runtime_checks Pragma
| Parameter(s) | Type of run-time check |
|---|---|
| s | Enables stack (frame) verification. |
| c | Reports when a value is assigned to a smaller data type that results in a data loss. |
| u | Reports when a variable is used before it is defined. |
These are the same letters used with the /RTC compiler option. For example:
#pragma runtime_checks
( "sc", restore )
Using the runtime_checks pragma with the empty string ("") is a special form of the directive:
When you use the off parameter, it turns the run-time error checks, listed in the table above, off.
When you use the restore parameter, it resets the run-time error checks to those that you specified with the /RTC compiler option.
#pragma runtime_checks
( "", off )
.
.
.
#pragma runtime_checks
( "", restore )