Does Integer Division by Zero Always Result in a Floating-Point Exception?

Integer Division by Zero Causing Floating Point Exception

Question:

Does integer division by zero always trigger a floating point exception?

Answer:

No, not all platforms report integer division by zero as a floating point exception. However, certain operating systems and C/C runtimes may handle this exception differently:

POSIX Platforms:

POSIX specifically requires that integer division by zero raises a SIGFPE (floating point exception) signal. POSIX also provides additional information that distinguishes it from other types of floating point exceptions, such as FPE_INTDIV_TRAP for division by zero.

Other Platforms:

• x64 Linux: Raises SIGFPE for all arithmetic errors, including integer division by zero.
• Windows: May report integer division by zero as a "floating-point division by zero" exception, depending on the platform and compiler settings.
• PPC: Raises a specific exception (0x7000) for floating point division by zero and does not trap for integer division by zero.

FP Exception Semantics:

Floating point exceptions are typically masked by default. This allows for operations like 0.0 / 0.0 to produce NaN without triggering an exception. However, this also means that the exception flag needs to be manually checked to determine if an exception occurred and of what type.

FP vs. Integer Error Detection:

Integer division does not have the option of producing NaN or Inf results, making it more straightforward to handle exceptions. However, on x86, out-of-range floating point values converted to integer with certain instructions may produce the "integer indefinite" value (INT_MIN) if the "floating-point invalid" exception is masked.

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