Procedures without LOCAL's don't restore ESP from EBP

[2B||!2B]

If a procedure has no LOCAL, it will not restore the stack from EBP.

Example of procedure with LOCAL

Code Select Expand

TESTPROC proc
LOCAL Dummy:DWORD

XOR EAX,EAX
ret

TESTPROC endp


Code Select Expand

PUSH EBP
MOV EBP,ESP
ADD ESP,-4
XOR EAX,EAX
MOV ESP,EBP
POP EBP
RETN 4


Removing LOCAL Dummy:DWORD would also make the procedure uses no MOV ESP,EBP before RET.

Code Select Expand

PUSH EBP
MOV EBP,ESP
XOR EAX,EAX
POP EBP
RETN 4


Is this the expected behavior or this is a bug?

[jj2007]

Expected behaviour. Masm and Watcom assemblers may differ slightly, e.g. using a leave before returning.

[2B||!2B]

I didn't know this until recently. I have used few PUSH's without re-balancing the stack and it was working with UASM v2.48 if I remember correctly. Must've been added recently...

[jj2007]

I didn't know this until recently. I have used few PUSH's without re-balancing the stack and it was working with UASM v2.48 if I remember correctly. Must've been added recently...

Check your non-volatile registers (esi edi ebx) saved via uses