GCC 4.9 #32 special value?

[Jens Vankeirsbilck <jens dot vankeirsbilck at kuleuven dot be>]

Hi all

While testing a GCC plugin I wrote, I came across something very strange.
The plugin inserts extra code into a C++ program on the RTL level. The code that produces the "magic" is as follows:

someMethod(){
	someInstructions()
	FOR_EACH_BB_FN(){
		someMoreInstructions()
	}
	evenMoreInstructions()
}

Now, the strange part:
Within the "FOR_EACH_BB_FN" loop, I create and emit an insn that contains a CONST_INT(VOIDmode, 32) rtx.
Once out of that "FOR_..." loop, the value of 32 gets changed to 28, for no apparent reason! I do not touch that emitted insn anymore, yet somehow the value of 32 is changed into 28.
Also, this only happens with the value 32. I also create the same kinds of insn's with values like 8, 64 or 262144 and they hold there value.

Can someone explain to me why this happens?

Thanks in advance.
With kind regard,
Ing. Jens Vankeirsbilck