From: Iain Buclaw Date: Tue, 25 Aug 2020 09:44:48 +0000 (+0200) Subject: d: Limit recursive expansion to a common global limit. X-Git-Tag: releases/gcc-10.3.0~976 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6f2ab69ae27aa07935e2be7b120472496114a549;p=thirdparty%2Fgcc.git d: Limit recursive expansion to a common global limit. Fixes both a bug where compilation would hang, and an issue where recursive template limits are hit too early. gcc/d/ChangeLog: * dmd/globals.h (Global): Add recursionLimit. * dmd/dmacro.c (Macro::expand): Limit recursive expansion to global.recursionLimit. * dmd/dtemplate.c (deduceType): Likewise. (TemplateInstance::tryExpandMembers): Likewise. (TemplateInstance::trySemantic3): Likewise. (TemplateMixin::semantic): Likewise. * dmd/expressionsem.c (ExpressionSemanticVisitor::visit): Likewise. * dmd/mtype.c (Type::noMember): Likewise. (TypeFunction::semantic): Likewise. * dmd/optimize.c (Expression_optimize): Likewise. gcc/testsuite/ChangeLog: * gdc.test/compilable/ice20092.d: New test. (cherry picked from commit 0f5c98b6a1a7eed281e359f40bc2e4326f2a2f56) --- diff --git a/gcc/d/dmd/dmacro.c b/gcc/d/dmd/dmacro.c index 77fe08add1f5..5a85866493de 100644 --- a/gcc/d/dmd/dmacro.c +++ b/gcc/d/dmd/dmacro.c @@ -226,11 +226,10 @@ void Macro::expand(OutBuffer *buf, size_t start, size_t *pend, { // limit recursive expansion static int nest; - static const int nestLimit = 1000; - if (nest > nestLimit) + if (nest > global.recursionLimit) { - error(Loc(), "DDoc macro expansion limit exceeded; more than %d " - "expansions.", nestLimit); + error(Loc(), "DDoc macro expansion limit exceeded; more than %d expansions.", + global.recursionLimit); return; } nest++; diff --git a/gcc/d/dmd/dtemplate.c b/gcc/d/dmd/dtemplate.c index b5e3662a9e30..9d211eb0340d 100644 --- a/gcc/d/dmd/dtemplate.c +++ b/gcc/d/dmd/dtemplate.c @@ -4337,6 +4337,13 @@ MATCH deduceType(RootObject *o, Scope *sc, Type *tparam, TemplateParameters *par void visit(ArrayLiteralExp *e) { + // https://issues.dlang.org/show_bug.cgi?id=20092 + if (e->elements && e->elements->dim && + e->type->toBasetype()->nextOf()->ty == Tvoid) + { + result = deduceEmptyArrayElement(); + return; + } if ((!e->elements || !e->elements->dim) && e->type->toBasetype()->nextOf()->ty == Tvoid && tparam->ty == Tarray) @@ -5932,10 +5939,10 @@ void TemplateInstance::tryExpandMembers(Scope *sc2) static int nest; // extracted to a function to allow windows SEH to work without destructors in the same function //printf("%d\n", nest); - if (++nest > 500) + if (++nest > global.recursionLimit) { global.gag = 0; // ensure error message gets printed - error("recursive expansion"); + error("recursive expansion exceeded allowed nesting limit"); fatal(); } @@ -5949,10 +5956,10 @@ void TemplateInstance::trySemantic3(Scope *sc2) // extracted to a function to allow windows SEH to work without destructors in the same function static int nest; //printf("%d\n", nest); - if (++nest > 300) + if (++nest > global.recursionLimit) { global.gag = 0; // ensure error message gets printed - error("recursive expansion"); + error("recursive expansion exceeded allowed nesting limit"); fatal(); } semantic3(sc2); @@ -6353,7 +6360,7 @@ Lerror: while (ti && !ti->deferred && ti->tinst) { ti = ti->tinst; - if (++nest > 500) + if (++nest > global.recursionLimit) { global.gag = 0; // ensure error message gets printed error("recursive expansion"); @@ -8440,7 +8447,7 @@ void TemplateMixin::semantic(Scope *sc) static int nest; //printf("%d\n", nest); - if (++nest > 500) + if (++nest > global.recursionLimit) { global.gag = 0; // ensure error message gets printed error("recursive expansion"); diff --git a/gcc/d/dmd/expressionsem.c b/gcc/d/dmd/expressionsem.c index 559c656e6540..5ec4683848e7 100644 --- a/gcc/d/dmd/expressionsem.c +++ b/gcc/d/dmd/expressionsem.c @@ -2900,7 +2900,7 @@ public: else { static int nest; - if (++nest > 500) + if (++nest > global.recursionLimit) { exp->error("recursive evaluation of %s", exp->toChars()); --nest; diff --git a/gcc/d/dmd/globals.h b/gcc/d/dmd/globals.h index 1094679b8376..855ba739b5d4 100644 --- a/gcc/d/dmd/globals.h +++ b/gcc/d/dmd/globals.h @@ -236,6 +236,8 @@ struct Global void* console; // opaque pointer to console for controlling text attributes + enum { recursionLimit = 500 }; // number of recursive template expansions before abort + /* Start gagging. Return the current number of gagged errors */ unsigned startGagging(); diff --git a/gcc/d/dmd/mtype.c b/gcc/d/dmd/mtype.c index aa1880624ceb..3fb16e000ef7 100644 --- a/gcc/d/dmd/mtype.c +++ b/gcc/d/dmd/mtype.c @@ -2202,7 +2202,7 @@ Expression *Type::noMember(Scope *sc, Expression *e, Identifier *ident, int flag static int nest; // https://issues.dlang.org/show_bug.cgi?id=17380 - if (++nest > 500) + if (++nest > global.recursionLimit) { ::error(e->loc, "cannot resolve identifier `%s`", ident->toChars()); --nest; @@ -5449,7 +5449,7 @@ Type *TypeFunction::semantic(Loc loc, Scope *sc) bool errors = false; - if (inuse > 500) + if (inuse > global.recursionLimit) { inuse = 0; ::error(loc, "recursive type"); diff --git a/gcc/d/dmd/optimize.c b/gcc/d/dmd/optimize.c index 2e702ba9d866..bae9d8e54031 100644 --- a/gcc/d/dmd/optimize.c +++ b/gcc/d/dmd/optimize.c @@ -19,6 +19,7 @@ #include "init.h" #include "enum.h" #include "ctfe.h" +#include "errors.h" Expression *semantic(Expression *e, Scope *sc); @@ -1256,10 +1257,18 @@ Expression *Expression_optimize(Expression *e, int result, bool keepLvalue) v.ret = e; // Optimize the expression until it can no longer be simplified. - while (ex != v.ret) + size_t b = 0; + while (1) { + if (b++ == global.recursionLimit) + { + e->error("infinite loop while optimizing expression"); + fatal(); + } ex = v.ret; ex->accept(&v); + if (ex == v.ret) + break; } return ex; } diff --git a/gcc/testsuite/gdc.test/compilable/ice20092.d b/gcc/testsuite/gdc.test/compilable/ice20092.d new file mode 100644 index 000000000000..ff2be374bd2d --- /dev/null +++ b/gcc/testsuite/gdc.test/compilable/ice20092.d @@ -0,0 +1,10 @@ +void foo() +{ + (void[1]).init.front; +} + +void front(T)(T[] a) +{ + static assert(is(T == void)); +} +