I once had a conversation with a friend about how to pronounce "roof". We sounded like a couple of dogs barking down the hallway -- until we got to the library and looked it up. (You can say it either way.)
You can char wood and turn it into charcoal, thus it has been charred, but the variable type "char" is short for character, which I have never heard pronounced any other way than care-actor. If you say char like charring wood, I will think you are using the verb "char", but if you say char like 'care', I will think you are using the short name of the character variable type.
But surely the context you will tell you that it is not a verb. If I walk up and say "Hey I've got this char array here, and blah blah"... I highly doubt you'll think I'm referring to a verb in that situation.
Huh; I thought even Americans said "character" with a short A at the start, and that more-or-less everyone pronounced "char" like "charred" or the same as "car".
Nope, it's pronounced like care-actor out here. And I've always called it "care." Then again I pronounce int as "eye en tee" rather than "in't"
Also, fun fact, Mid Western American english is closer to an old English accent than modern British. What is commonly thought of as a british accent (a london accent, I think) only came about in the 16 or 1700s when the nobels of london began dropping the 'r' in words. That is, they became non-rhotic while the Americas remained rhotic. Interestingly enough. while non-rhotic english caught on in england and most of scotland, Ireland's english remained rhotic.
Another fun fact: Back in the days of Henry VIII, there was very little standardisation of spelling, so he spelled his name HENZY VIII.
 This might also be interesting: I know because I've seen actual documents (originals, not copies) signed by him, some by his son Edward and also his daughter Mary's marriage contract to Philip of Spain. My history teacher took my class to the National Archives some months back. I didn't really appreciate it at the time, but that was an amazing experience.