/Qimprecise_fwaits (Remove fwaits Inside Try Blocks)

Removes the fwait commands internal to try blocks when you use the /fp:except compiler option.

Syntax

/Qimprecise_fwaits

Remarks

This option has no effect if /fp:except isn't also specified. If you specify the /fp:except option, the compiler will insert a fwait instruction around each line of code in a try block. In this way, the compiler can identify the specific line of code that produces an exception. /Qimprecise_fwaits removes internal fwait instructions, leaving only the waits around the try block. It improves performance, but the compiler can only show which try block causes an exception, not which line.

To set this compiler option in the Visual Studio development environment

  1. Open the project's Property Pages dialog box. For details, see Set C++ compiler and build properties in Visual Studio.

  2. Select the Configuration Properties > C/C++ > Command Line property page.

  3. Enter the compiler option in the Additional Options box.

To set this compiler option programmatically

See also

/Q Options (Low-Level Operations)
MSVC Compiler Options
MSVC Compiler Command-Line Syntax