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Fix __builtin_{smulll,saddll}_overflow() usage #2205

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Merged
merged 1 commit into from
May 2, 2019
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Fix __builtin_{smulll,saddll}_overflow() usage #2205

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4 changes: 2 additions & 2 deletions CoreFoundation/String.subproj/CFString.c
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Original file line number Diff line number Diff line change
Expand Up @@ -6442,9 +6442,9 @@ reswtch:switch (ch) {
return true;
}
case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': {
int64_t number = 0;
long long number = 0;
do {
if (__builtin_smulll_overflow(number, 10, &number) || __builtin_saddll_overflow(number, ch - '0', &number)) {
if (__builtin_smulll_overflow(number, 10, &number) || __builtin_saddll_overflow(number, ch - '0', &number) || number > INT64_MAX) {
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Isn't this a tautological comparison? number is a long long which is signed. INT64_MAX is signed. So the value of the condition is always false.

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long long is only defined to be at least 64 bits but could be more if ever ported to other platforms. This is a bit of a nit-picking change but it should make it technically correct.

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What platform(s) currently define it to something other than 64-bit?

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I'm okay taking pedantic correctness fixes, since this is code intended to be portable.

if (errorPtr) *errorPtr = __CFCreateOverflowError();
return false;
}
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