Bug 17949 – ICE in dmangle.d

Dustmite and manual reduction of the same assert in a large codebase. % cat break.d auto foo() { int high; auto window = S(); window.map!(bs => bs.map!(bar => high)); } struct S { auto front() { return [3]; } } template ElementType(R) { static if (is(typeof(R.front.init) T)) alias ElementType = T; } template map(alias fun) { void map(Range)(Range) { alias RE = ElementType!Range; assert(!is(typeof(fun(RE.init)))); MapResult!(fun, Range)(); } } int front(int[] a); struct MapResult(alias fun, Range) { Range _input; void front() { fun(_input.front); } } % dmd -o- break.d DMD v2.077.0-rc.1-68-g0342fe8c7 DEBUG core.exception.AssertError@ddmd/dmangle.d(374): Assertion failure ---------------- 4 dmd 0x0000000100950e91 _d_assertp + 117 5 dmd 0x000000010074512e _ZN7Mangler14mangleFuncTypeEP12TypeFunctionS1_hP4Type + 230 6 dmd 0x00000001007457a0 _ZN7Mangler10mangleFuncEP15FuncDeclarationb + 120 7 dmd 0x0000000100745703 _ZN7Mangler12mangleParentEP7Dsymbol + 267 8 dmd 0x000000010074656c _ZN7Mangler5visitEP7Dsymbol + 28 9 dmd 0x000000010083b639 _ZN7Visitor5visitEP12ScopeDsymbol + 33 10 dmd 0x000000010083b661 _ZN7Visitor5visitEP19TemplateDeclaration + 33 11 dmd 0x0000000100774d01 _ZN19TemplateDeclaration6acceptEP7Visitor + 33 12 dmd 0x0000000100744d61 _ZN7Mangler12mangleSymbolEP7Dsymbol + 33 13 dmd 0x00000001007464bb _ZN7Mangler22mangleTemplateInstanceEP16TemplateInstance + 1275 14 dmd 0x00000001007456b6 _ZN7Mangler12mangleParentEP7Dsymbol + 190 15 dmd 0x000000010074656c _ZN7Mangler5visitEP7Dsymbol + 28 16 dmd 0x0000000100745f29 _ZN7Mangler5visitEP20AggregateDeclaration + 281 17 dmd 0x000000010083b7f1 _ZN7Visitor5visitEP17StructDeclaration + 33 18 dmd 0x0000000100755191 _ZN17StructDeclaration6acceptEP7Visitor + 33 19 dmd 0x0000000100744d61 _ZN7Mangler12mangleSymbolEP7Dsymbol + 33 20 dmd 0x00000001007454a0 _ZN7Mangler5visitEP10TypeStruct + 48 21 dmd 0x00000001008038f9 _ZN10TypeStruct6acceptEP7Visitor + 33 22 dmd 0x0000000100744d9a _ZN7Mangler10mangleTypeEP4Type + 50 23 dmd 0x0000000100744e34 _ZN7Mangler13visitWithMaskEP4Typeh + 68 24 dmd 0x0000000100747045 _ZN7Mangler5visitEP9Parameter + 349 25 dmd 0x0000000100807a91 _ZN9Parameter6acceptEP7Visitor + 33 26 dmd 0x0000000100746ee3 int ddmd.dmangle.Mangler.paramsToDecoBuffer(ddmd.root.array.Array!(ddmd.mtype.Parameter).Array*).paramsToDecoBufferDg(ulong, ddmd.mtype.Parameter) + 35 27 dmd 0x0000000100807da5 int ddmd.mtype.Parameter._foreach(ddmd.root.array.Array!(ddmd.mtype.Parameter).Array*, int delegate(ulong, ddmd.mtype.Parameter), ulong*) + 253 28 dmd 0x0000000100746ebd _ZN7Mangler18paramsToDecoBufferEP5ArrayIP9ParameterE + 37 29 dmd 0x000000010074535d _ZN7Mangler14mangleFuncTypeEP12TypeFunctionS1_hP4Type + 789 30 dmd 0x0000000100745044 _ZN7Mangler5visitEP12TypeFunction + 44 31 dmd 0x00000001007ff1e1 _ZN12TypeFunction6acceptEP7Visitor + 33 32 dmd 0x0000000100744d9a _ZN7Mangler10mangleTypeEP4Type + 50 33 dmd 0x0000000100744e34 _ZN7Mangler13visitWithMaskEP4Typeh + 68 34 dmd 0x000000010074716e _Z14mangleToBufferP4TypeP9OutBuffer + 102 35 dmd 0x000000010083574e ddmd.mtype.Type ddmd.typesem.merge(ddmd.mtype.Type) + 286 36 dmd 0x0000000100834b08 _ZN19TypeSemanticVisitor5visitEP12TypeFunction + 5328 37 dmd 0x00000001007ff1e1 _ZN12TypeFunction6acceptEP7Visitor + 33 38 dmd 0x00000001008314f6 _Z12typeSemanticP4Type3LocP5Scope + 86 39 dmd 0x00000001007671df _ZN22DsymbolSemanticVisitor23funcDeclarationSemanticEP15FuncDeclaration + 2711 40 dmd 0x0000000100768afc _ZN22DsymbolSemanticVisitor5visitEP15FuncDeclaration + 28 41 dmd 0x00000001007bcd11 _ZN15FuncDeclaration6acceptEP7Visitor + 33 42 dmd 0x0000000100759b70 _Z15dsymbolSemanticP7DsymbolP5Scope + 64 43 dmd 0x0000000100700568 _Z14buildXopEqualsP17StructDeclarationP5Scope + 1512 44 dmd 0x000000010076ad4f _ZN22DsymbolSemanticVisitor5visitEP17StructDeclaration + 1927 45 dmd 0x0000000100755191 _ZN17StructDeclaration6acceptEP7Visitor + 33 46 dmd 0x0000000100759b70 _Z15dsymbolSemanticP7DsymbolP5Scope + 64 47 dmd 0x0000000100781ae8 _ZN16TemplateInstance13expandMembersEP5Scope + 240 48 dmd 0x0000000100781b62 _ZN16TemplateInstance16tryExpandMembersEP5Scope + 98 49 dmd 0x000000010076ea6e void ddmd.dsymbolsem.templateInstanceSemantic(ddmd.dtemplate.TemplateInstance, ddmd.dscope.Scope*, ddmd.root.array.Array!(ddmd.expression.Expression).Array*) + 2422 50 dmd 0x0000000100765d2a _ZN22DsymbolSemanticVisitor5visitEP16TemplateInstance + 34 51 dmd 0x0000000100781c29 _ZN16TemplateInstance6acceptEP7Visitor + 33 52 dmd 0x0000000100759b70 _Z15dsymbolSemanticP7DsymbolP5Scope + 64 53 dmd 0x000000010079db20 _ZN25ExpressionSemanticVisitor5visitEP8ScopeExp + 1264 54 dmd 0x000000010078fd61 _ZN8ScopeExp6acceptEP7Visitor + 33 55 dmd 0x00000001007b53fa _Z18expressionSemanticP10ExpressionP5Scope + 66 56 dmd 0x000000010083e3c1 _ZN24StatementSemanticVisitor5visitEP12ExpStatement + 81 57 dmd 0x000000010082c15e _ZN12ExpStatement6acceptEP7Visitor + 30 58 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 59 dmd 0x000000010083e683 _ZN24StatementSemanticVisitor5visitEP17CompoundStatement + 251 60 dmd 0x000000010082c98e _ZN17CompoundStatement6acceptEP7Visitor + 30 61 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 62 dmd 0x000000010075c520 _ZN16Semantic3Visitor5visitEP15FuncDeclaration + 4960 63 dmd 0x00000001007bcd11 _ZN15FuncDeclaration6acceptEP7Visitor + 33 64 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 65 dmd 0x000000010075af17 _ZN16Semantic3Visitor5visitEP16TemplateInstance + 359 66 dmd 0x0000000100781c29 _ZN16TemplateInstance6acceptEP7Visitor + 33 67 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 68 dmd 0x0000000100781bda _ZN16TemplateInstance12trySemantic3EP5Scope + 98 69 dmd 0x000000010076eedd void ddmd.dsymbolsem.templateInstanceSemantic(ddmd.dtemplate.TemplateInstance, ddmd.dscope.Scope*, ddmd.root.array.Array!(ddmd.expression.Expression).Array*) + 3557 70 dmd 0x00000001007750c8 void ddmd.dtemplate.functionResolve(ddmd.declaration.Match*, ddmd.dsymbol.Dsymbol, ddmd.globals.Loc, ddmd.dscope.Scope*, ddmd.root.array.Array!(ddmd.root.rootobject.RootObject).Array*, ddmd.mtype.Type, ddmd.root.array.Array!(ddmd.expression.Expression).Array*) + 376 71 dmd 0x00000001007bd4cc _Z15resolveFuncCall3LocP5ScopeP7DsymbolP5ArrayIP10RootObjectEP4TypePS4_IP10ExpressionEi + 188 72 dmd 0x00000001007a305e _ZN25ExpressionSemanticVisitor5visitEP7CallExp + 10718 73 dmd 0x0000000100793a79 _ZN7CallExp6acceptEP7Visitor + 33 74 dmd 0x00000001007b53fa _Z18expressionSemanticP10ExpressionP5Scope + 66 75 dmd 0x0000000100788a94 _Z21resolveUFCSPropertiesP5ScopeP10ExpressionS2_ + 1044 76 dmd 0x00000001007a6fd1 _ZN25ExpressionSemanticVisitor5visitEP22DotTemplateInstanceExp + 65 77 dmd 0x0000000100793369 _ZN22DotTemplateInstanceExp6acceptEP7Visitor + 33 78 dmd 0x00000001007b53fa _Z18expressionSemanticP10ExpressionP5Scope + 66 79 dmd 0x0000000100848235 _ZN24StatementSemanticVisitor5visitEP15ReturnStatement + 1397 80 dmd 0x000000010082eaf9 _ZN15ReturnStatement6acceptEP7Visitor + 33 81 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 82 dmd 0x000000010075c520 _ZN16Semantic3Visitor5visitEP15FuncDeclaration + 4960 83 dmd 0x000000010083bca1 _ZN7Visitor5visitEP22FuncLiteralDeclaration + 33 84 dmd 0x00000001007bebf1 _ZN22FuncLiteralDeclaration6acceptEP7Visitor + 33 85 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 86 dmd 0x000000010075af17 _ZN16Semantic3Visitor5visitEP16TemplateInstance + 359 87 dmd 0x0000000100781c29 _ZN16TemplateInstance6acceptEP7Visitor + 33 88 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 89 dmd 0x0000000100781bda _ZN16TemplateInstance12trySemantic3EP5Scope + 98 90 dmd 0x000000010076eedd void ddmd.dsymbolsem.templateInstanceSemantic(ddmd.dtemplate.TemplateInstance, ddmd.dscope.Scope*, ddmd.root.array.Array!(ddmd.expression.Expression).Array*) + 3557 91 dmd 0x00000001007750c8 void ddmd.dtemplate.functionResolve(ddmd.declaration.Match*, ddmd.dsymbol.Dsymbol, ddmd.globals.Loc, ddmd.dscope.Scope*, ddmd.root.array.Array!(ddmd.root.rootobject.RootObject).Array*, ddmd.mtype.Type, ddmd.root.array.Array!(ddmd.expression.Expression).Array*) + 376 92 dmd 0x00000001007bd4cc _Z15resolveFuncCall3LocP5ScopeP7DsymbolP5ArrayIP10RootObjectEP4TypePS4_IP10ExpressionEi + 188 93 dmd 0x00000001007a305e _ZN25ExpressionSemanticVisitor5visitEP7CallExp + 10718 94 dmd 0x0000000100793a79 _ZN7CallExp6acceptEP7Visitor + 33 95 dmd 0x00000001007b53fa _Z18expressionSemanticP10ExpressionP5Scope + 66 96 dmd 0x000000010083e3c1 _ZN24StatementSemanticVisitor5visitEP12ExpStatement + 81 97 dmd 0x000000010082c15e _ZN12ExpStatement6acceptEP7Visitor + 30 98 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 99 dmd 0x000000010083e683 _ZN24StatementSemanticVisitor5visitEP17CompoundStatement + 251 100 dmd 0x000000010082c98e _ZN17CompoundStatement6acceptEP7Visitor + 30 101 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 102 dmd 0x000000010075c520 _ZN16Semantic3Visitor5visitEP15FuncDeclaration + 4960 103 dmd 0x00000001007bcd11 _ZN15FuncDeclaration6acceptEP7Visitor + 33 104 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 105 dmd 0x000000010075f3e2 _ZN16Semantic3Visitor5visitEP20AggregateDeclaration + 210 106 dmd 0x000000010083b7f1 _ZN7Visitor5visitEP17StructDeclaration + 33 107 dmd 0x0000000100755191 _ZN17StructDeclaration6acceptEP7Visitor + 33 108 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 109 dmd 0x000000010075af17 _ZN16Semantic3Visitor5visitEP16TemplateInstance + 359 110 dmd 0x0000000100781c29 _ZN16TemplateInstance6acceptEP7Visitor + 33 111 dmd 0x0000000100829fb0 _Z9semantic3P7DsymbolP5Scope + 64 112 dmd 0x0000000100781bda _ZN16TemplateInstance12trySemantic3EP5Scope + 98 113 dmd 0x000000010076eedd void ddmd.dsymbolsem.templateInstanceSemantic(ddmd.dtemplate.TemplateInstance, ddmd.dscope.Scope*, ddmd.root.array.Array!(ddmd.expression.Expression).Array*) + 3557 114 dmd 0x0000000100765d2a _ZN22DsymbolSemanticVisitor5visitEP16TemplateInstance + 34 115 dmd 0x0000000100781c29 _ZN16TemplateInstance6acceptEP7Visitor + 33 116 dmd 0x0000000100759b70 _Z15dsymbolSemanticP7DsymbolP5Scope + 64 117 dmd 0x000000010079db20 _ZN25ExpressionSemanticVisitor5visitEP8ScopeExp + 1264 118 dmd 0x000000010078fd61 _ZN8ScopeExp6acceptEP7Visitor + 33 119 dmd 0x00000001007b53fa _Z18expressionSemanticP10ExpressionP5Scope + 66 120 dmd 0x000000010083e3c1 _ZN24StatementSemanticVisitor5visitEP12ExpStatement + 81 121 dmd 0x000000010082c15e _ZN12ExpStatement6acceptEP7Visitor + 30 122 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 123 dmd 0x000000010083e683 _ZN24StatementSemanticVisitor5visitEP17CompoundStatement + 251 124 dmd 0x000000010082c98e _ZN17CompoundStatement6acceptEP7Visitor + 30 125 dmd 0x000000010083e2a2 _Z17statementSemanticP9StatementP5Scope + 66 126 dmd 0x000000010075c520 _ZN16Semantic3Visitor5visitEP15FuncDeclaration + 4960 127 dmd 0x00000001007bcd11 _ZN15FuncDeclaration6acceptEP7Visitor + 33

See https://run.dlang.io/is/7Vljp1 This needs a better test case. I can't reproduce it.

I can't repro it, either. This PR may have fixed it: https://github.com/dlang/dmd/commit/6517be5b3fe7bdcd8d9e6aa62eee9238bf8c13b9 with the addition of the `LINK.system` case. The assert fail in the test case was probably the `default: assert(0);` I'm going to mark this worksforme. If there are further problems with it, please reopen.