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Shifting long long value more than 63 bits is UB #580

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Shifting long long value more than 63 bits is UB #580

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2 changes: 1 addition & 1 deletion ddprof-lib/src/main/cpp/arguments.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -440,7 +440,7 @@ const char *Arguments::file() {
// Should match statically computed HASH(arg)
long long Arguments::hash(const char *arg) {
long long h = 0;
for (int shift = 0; *arg != 0; shift += 5) {
for (int shift = 0; *arg != 0 && shift < 60; shift += 5) {
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@chatgpt-codex-connector chatgpt-codex-connector Bot Jun 5, 2026

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P2 Badge Reject overlong option suffixes

For arguments longer than 12 characters, this now silently ignores the rest of the option name, so malformed inputs whose first twelve bytes collide with a valid CASE are accepted instead of being recorded as _unknown_arg. For example, start x hashes the same as start because the seven spaces occupy the remaining hashed slots and the trailing x is discarded, which sets ACTION_START with no unknown-argument warning; overlong names should instead produce a non-matching hash once *arg remains after the 12th character.

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h |= (*arg++ & 31LL) << shift;
}
return h;
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