code_seg

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The latest version of this topic can be found at code_seg. Specifies the text segment where functions are stored in the .obj file.

Syntax

#pragma code_seg
( [ [ { push | pop }, ] [ identifier, ] ] [ "segment-name" [, "segment-class" ] )  

Remarks

The code_seg pragma directive does not control placement of object code generated for instantiated templates, nor code generated implicitly by the compiler—for example, special member functions. We recommend that you use the __declspec(code_seg(...)) attribute instead because it gives you control over placement of all object code. This includes compiler-generated code.

A segment in an .obj file is a named block of data that's loaded into memory as a unit. A text segment is a segment that contains executable code. In this article, the terms segment and section are used interchangeably.

The code_seg pragma directive tells the compiler to put all subsequent object code from the translation unit into a text segment named segment-name. By default, the text segment used for functions in an .obj file is named .text.

A code_seg pragma directive without parameters resets the text segment name for the subsequent object code to .text.

Push (optional)
Puts a record on the internal compiler stack. A push can have an identifier and segment-name.

pop (optional)
Removes a record from the top of the internal compiler stack.

identifier (optional)
When used with push, assigns a name to the record on the internal compiler stack. When used with pop, pops records off the internal stack until identifier is removed; if identifier is not found on the internal stack, nothing is popped.

identifier enables multiple records to be popped with just one pop command.

"segment-name" (optional)
The name of a segment. When used with pop, the stack is popped and segment-name becomes the active text segment name.

"segment-class" (optional)
Ignored, but included for compatibility with versions of C++ earlier than version 2.0.

You can use the DUMPBIN.EXE application to view .obj files. Versions of DUMPBIN for each supported target architecture are included with Visual Studio.

Example

This example shows how to use the code_seg pragma directive to control where object code is put:

// pragma_directive_code_seg.cpp  
void func1() {                  // stored in .text  
}  
  
#pragma code_seg(".my_data1")  
void func2() {                  // stored in my_data1  
}  
  
#pragma code_seg(push, r1, ".my_data2")  
void func3() {                  // stored in my_data2  
}  
  
#pragma code_seg(pop, r1)      // stored in my_data1  
void func4() {  
}  
  
int main() {  
}  

For a list of names that should not be used to create a section, see /SECTION.

You can also specify sections for initialized data (data_seg), uninitialized data (bss_seg), and const variables (const_seg).

See Also

code_seg (__declspec)
Pragma Directives and the __Pragma Keyword