What was the most dangerous programming mistake you have made in C?

Question

I am an intermediate C programmer. If you have made any coding mistake that you came to know later that it was the most hazardous / harmful to the total application please share

Answer 1

Passing virtual address to the DMA engine was a worst one, not exactly C related, but i assume that 99% of DMA related stuff written in C so it's kind of match. This small error lead to memory corruption that took me 1.5 month to find.