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Compiler Warning (level 1) C4124


The latest version of this topic can be found at Compiler Warning (level 1) C4124.

__fastcall with stack checking is inefficient

The __fastcall keyword was used with stack checking enabled.

The __fastcall convention generates faster code, but stack checking causes slower code. When using __fastcall, turn off stack checking with the check_stack pragma or /Gs.

This warning is issued only for the first function declared under these conditions.