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u8 Key; u8 VarItem; switch (Key) { case Kb_0 : ... case Kb_1 : ... case Kb_2 : ... case Kb_3 : ... case Kb_4 : ... case Kb_5 : ... case Kb_6 : ... case Kb_7 : ... case Kb_8 : ... case Kb_9 : ... case Kb_Min : ... case Kb_Enter : switch (VarItem) { case 0 : ... case 1 : ... case 2 : ... } }
When I compile above I got one warning warning: #516-D: transfer of control bypasses initialisation off: in the line near switch(VarItem). What is the meaning of this warning. When I ignore it, all works, but I do not like warnings ...
May be the compiler sees variable VarItem as not initialized
You showed too little code.
One of your case alternatives assigns a value to one of your variables, and the compiler can not know if this is a state machine that is guaranteed to pass this specific state.
Thanks for response.
Problem solved ! but I do not see any reason to generate a warning. The source code is a C++ file !
Following code gives a warning.
void Test(u8 num) { switch (num) { case 1 : long test = 12; break; case 2 : break; } }
following code does not.
void Test(u8 num) { long test; switch (num) { case 1 : test = 12; break; case 2 : break; } }
It seems that when you declare a variable in a switch, the compiler generates a warning. I do not see why, but however, the problem is solved ...
Luc Vercruysse
"I do not see any reason to generate a warning. The source code is a C++ file!"
Lots of C++ source files generate warnings! It's up to you to fix your source code!
A warning seems absolutely in order here! in case 1, you both define and initialise 'test', but in case 2, you skip both the definition and the initialisation - what do you expect the compiler to make of this?!
The compiler warnings describes exactly what you are doing: "transfer of control" = the jump to case 2; "bypasses initialisation" - well, obviously the initialisation at case 1 is bypassed when the execution jumps straight to case 2, isn't it?!
Correct ! Shame on me ....
Luc
"... I do not see why ..."
A new definition can occur within a brace-enclosed block:
void Test(u8 num) { switch (num) { case 1: { long test = 12; break; } case 2: break; } }