Bug 17955 – compiler segfault in DsymbolSemanticVisitor::visit(UnittestDeclaration*)

The following code causes dmd to segfault. The regression was introduced by https://github.com/dlang/dmd/pull/7198 Sorry for the large test case, couldn't seem to get it any smaller than this: alias Alias(alias a) = a; template isISOExtStringSerializable(T) { enum isISOExtStringSerializable = T.fromISOExtString(""); } template RedisObjectCollection(){} struct RedisStripped(T, bool strip_id = true) { alias unstrippedMemberIndices = indicesOf!(Select!(strip_id, isRedisTypeAndNotID, isRedisType), T.tupleof); } template indicesOf(alias PRED, T...) { template impl(size_t i) { static if (PRED!T) impl TypeTuple; } alias indicesOf = impl!0; } template isRedisType(alias F) { enum isRedisType = toRedis!(typeof(F)); } template isRedisTypeAndNotID(){} string toRedis(T)() { static if (isISOExtStringSerializable!T) return; } struct User { SysTime resetCodeExpireTime; } class RedisUserManController { RedisObjectCollection!(RedisStripped!User) m_users; } class TimeZone { abstract bool hasDST(); } class SimpleTimeZone : TimeZone { unittest {} immutable(SimpleTimeZone) fromISOExtString(S)(S) { new SimpleTimeZone; } } struct SysTime { static fromISOExtString(S)(S) { dstring zoneStr; try SimpleTimeZone.fromISOExtString(zoneStr); catch DateTimeException; } } template Select(bool condition, T...) { alias Select = Alias!(T[condition]); }

Commits pushed to master at https://github.com/dlang/dmd https://github.com/dlang/dmd/commit/a32b62f9415c65df9186037fbfe2f9acc1f5be56 fix Issue 17955 - compiler segfault in DsymbolSemanticVisitor::visit(UnittestDeclaration*) https://github.com/dlang/dmd/commit/56e48617fa91c80555abdcb5251861d3ed4099a7 Merge pull request #7277 from WalterBright/fix17955 fix Issue 17955 - compiler segfault in DsymbolSemanticVisitor::visit(… merged-on-behalf-of: Iain Buclaw <[email protected]>

*** Issue 18012 has been marked as a duplicate of this issue. ***

Commit pushed to stable at https://github.com/dlang/dmd https://github.com/dlang/dmd/commit/a41e3d26d62d498551abeb0da10c7356731b0fe7 Merge pull request #7277 from WalterBright/fix17955 fix Issue 17955 - compiler segfault in DsymbolSemanticVisitor::visit(… merged-on-behalf-of: Iain Buclaw <[email protected]>

Commit pushed to master at https://github.com/dlang/dmd https://github.com/dlang/dmd/commit/a41e3d26d62d498551abeb0da10c7356731b0fe7 Merge pull request #7277 from WalterBright/fix17955

Commits pushed to stable at https://github.com/dlang/dmd https://github.com/dlang/dmd/commit/a32b62f9415c65df9186037fbfe2f9acc1f5be56 fix Issue 17955 - compiler segfault in DsymbolSemanticVisitor::visit(UnittestDeclaration*) https://github.com/dlang/dmd/commit/56e48617fa91c80555abdcb5251861d3ed4099a7 Merge pull request #7277 from WalterBright/fix17955