Compiler bugs?

I've been writing code, in one form or other, for some 30 years now. And over all that time, I've found exactly two compiler bugs, and one of those is kinda grey area anyway.

First one was a C compiler for C51 processors. The bug was that when a did something like this;

int var;

void func()

{ var = var*2; }

...

var = 3;

func();

printf("var=%i\n", var);

It would print out 3. Whether this actually counts as bug (variable wasn't volatile, after all) is another issue, but this did take a few moments of head scratching to figure out.

Another one was with Microsoft Visual Studio 6 (or might been few versions newer MSVC too) or so. I don't remember the exact details here, but somehow, when #including things is a very specific order, compiler (well, pre-processor) decided to completely drop one of the included files from compilation, resulting a very, very strange error complaining about undeclared classes/namespaces/whatever (again, exact details escape me).

This one took again few hours to figure out (I had to actually make compiler to print out pre-processed intermediate output to find out what exactly happened), and just switching include order of two files (one that was dropped and another) fixed the issue.

Unfortunately, this was part of very complex project, so making simplified case of this to report the issue wasn't possibly, so I never submitted a bug report.

What am I trying to say here?

Do you suspect that error is a compiler bug? I am willing to bet that it isn't - it's your bug.

Yet, even then, I am a bit... shall we say, reluctant, to upgrade the compiler I'm using for my ARM builds. Although the possibility of finding an actual compiler bug is nearly zero, possibility of triggering some obscure bug in some part of (my!) old code because some detail somewhere changed doesn't make a fun possibility...