PR9793: Treat substitution as an instantiation step for the purpose of the
-ftemplate-depth limit. There are various ways to get an infinite (or merely
huge) stack of substitutions with no intervening instantiations. This is also
consistent with gcc's behavior.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159907 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index cfc55e5..6dbf704 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -3383,6 +3383,8 @@
= ArgList.getInnermost();
InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first,
Innermost.second);
+ if (Inst)
+ return ExprError();
ExprResult Result;
{
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index 77695c1..4605e01 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -1990,6 +1990,8 @@
TemplateArgLists.addOuterTemplateArguments(0, 0);
InstantiatingTemplate Inst(*this, TemplateLoc, Template);
+ if (Inst)
+ return QualType();
CanonType = SubstType(Pattern->getUnderlyingType(),
TemplateArgLists, AliasTemplate->getLocation(),
AliasTemplate->getDeclName());
@@ -2550,6 +2552,8 @@
Template, Converted.data(),
Converted.size(),
SourceRange(TemplateLoc, RAngleLoc));
+ if (Inst)
+ return 0;
Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs,
@@ -2599,6 +2603,8 @@
Template, Converted.data(),
Converted.size(),
SourceRange(TemplateLoc, RAngleLoc));
+ if (Inst)
+ return ExprError();
Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
EnterExpressionEvaluationContext Unevaluated(SemaRef, Sema::Unevaluated);
@@ -2648,6 +2654,8 @@
Template, Converted.data(),
Converted.size(),
SourceRange(TemplateLoc, RAngleLoc));
+ if (Inst)
+ return TemplateName();
Sema::ContextRAII SavedContext(SemaRef, Template->getDeclContext());
// Substitute into the nested-name-specifier first,
@@ -2781,6 +2789,8 @@
InstantiatingTemplate Inst(*this, TemplateLoc, Template,
NTTP, Converted.data(), Converted.size(),
SourceRange(TemplateLoc, RAngleLoc));
+ if (Inst)
+ return true;
TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
Converted.data(), Converted.size());
@@ -2913,6 +2923,8 @@
InstantiatingTemplate Inst(*this, TemplateLoc, Template,
TempParm, Converted.data(), Converted.size(),
SourceRange(TemplateLoc, RAngleLoc));
+ if (Inst)
+ return true;
TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
Converted.data(), Converted.size());
@@ -3144,6 +3156,8 @@
InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param,
Converted.data(), Converted.size(),
SourceRange(TemplateLoc, RAngleLoc));
+ if (Instantiating)
+ return true;
// Check the default template argument.
if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc,
diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index 8973916..7416d12 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -156,11 +156,11 @@
case ExceptionSpecInstantiation:
case DefaultTemplateArgumentInstantiation:
case DefaultFunctionArgumentInstantiation:
- return true;
-
case ExplicitTemplateArgumentSubstitution:
case DeducedTemplateArgumentSubstitution:
case PriorTemplateArgumentSubstitution:
+ return true;
+
case DefaultTemplateArgumentChecking:
return false;
}
@@ -252,8 +252,7 @@
SavedInNonInstantiationSFINAEContext(
SemaRef.InNonInstantiationSFINAEContext)
{
- Invalid = CheckInstantiationDepth(PointOfInstantiation,
- InstantiationRange);
+ Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
if (!Invalid) {
ActiveTemplateInstantiation Inst;
Inst.Kind = Kind;
@@ -282,21 +281,19 @@
SavedInNonInstantiationSFINAEContext(
SemaRef.InNonInstantiationSFINAEContext)
{
- Invalid = false;
-
- ActiveTemplateInstantiation Inst;
- Inst.Kind = ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution;
- Inst.PointOfInstantiation = PointOfInstantiation;
- Inst.Entity = reinterpret_cast<uintptr_t>(PartialSpec);
- Inst.TemplateArgs = TemplateArgs;
- Inst.NumTemplateArgs = NumTemplateArgs;
- Inst.DeductionInfo = &DeductionInfo;
- Inst.InstantiationRange = InstantiationRange;
- SemaRef.InNonInstantiationSFINAEContext = false;
- SemaRef.ActiveTemplateInstantiations.push_back(Inst);
-
- assert(!Inst.isInstantiationRecord());
- ++SemaRef.NonInstantiationEntries;
+ Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
+ if (!Invalid) {
+ ActiveTemplateInstantiation Inst;
+ Inst.Kind = ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution;
+ Inst.PointOfInstantiation = PointOfInstantiation;
+ Inst.Entity = reinterpret_cast<uintptr_t>(PartialSpec);
+ Inst.TemplateArgs = TemplateArgs;
+ Inst.NumTemplateArgs = NumTemplateArgs;
+ Inst.DeductionInfo = &DeductionInfo;
+ Inst.InstantiationRange = InstantiationRange;
+ SemaRef.InNonInstantiationSFINAEContext = false;
+ SemaRef.ActiveTemplateInstantiations.push_back(Inst);
+ }
}
Sema::InstantiatingTemplate::InstantiatingTemplate(Sema &SemaRef,
@@ -310,7 +307,6 @@
SemaRef.InNonInstantiationSFINAEContext)
{
Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
-
if (!Invalid) {
ActiveTemplateInstantiation Inst;
Inst.Kind
@@ -336,21 +332,19 @@
SavedInNonInstantiationSFINAEContext(
SemaRef.InNonInstantiationSFINAEContext)
{
- Invalid = false;
-
- ActiveTemplateInstantiation Inst;
- Inst.Kind = ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution;
- Inst.PointOfInstantiation = PointOfInstantiation;
- Inst.Template = Template;
- Inst.Entity = reinterpret_cast<uintptr_t>(Param);
- Inst.TemplateArgs = TemplateArgs;
- Inst.NumTemplateArgs = NumTemplateArgs;
- Inst.InstantiationRange = InstantiationRange;
- SemaRef.InNonInstantiationSFINAEContext = false;
- SemaRef.ActiveTemplateInstantiations.push_back(Inst);
-
- assert(!Inst.isInstantiationRecord());
- ++SemaRef.NonInstantiationEntries;
+ Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
+ if (!Invalid) {
+ ActiveTemplateInstantiation Inst;
+ Inst.Kind = ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution;
+ Inst.PointOfInstantiation = PointOfInstantiation;
+ Inst.Template = Template;
+ Inst.Entity = reinterpret_cast<uintptr_t>(Param);
+ Inst.TemplateArgs = TemplateArgs;
+ Inst.NumTemplateArgs = NumTemplateArgs;
+ Inst.InstantiationRange = InstantiationRange;
+ SemaRef.InNonInstantiationSFINAEContext = false;
+ SemaRef.ActiveTemplateInstantiations.push_back(Inst);
+ }
}
Sema::InstantiatingTemplate::
@@ -364,20 +358,19 @@
SavedInNonInstantiationSFINAEContext(
SemaRef.InNonInstantiationSFINAEContext)
{
- Invalid = false;
- ActiveTemplateInstantiation Inst;
- Inst.Kind = ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution;
- Inst.PointOfInstantiation = PointOfInstantiation;
- Inst.Template = Template;
- Inst.Entity = reinterpret_cast<uintptr_t>(Param);
- Inst.TemplateArgs = TemplateArgs;
- Inst.NumTemplateArgs = NumTemplateArgs;
- Inst.InstantiationRange = InstantiationRange;
- SemaRef.InNonInstantiationSFINAEContext = false;
- SemaRef.ActiveTemplateInstantiations.push_back(Inst);
-
- assert(!Inst.isInstantiationRecord());
- ++SemaRef.NonInstantiationEntries;
+ Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
+ if (!Invalid) {
+ ActiveTemplateInstantiation Inst;
+ Inst.Kind = ActiveTemplateInstantiation::PriorTemplateArgumentSubstitution;
+ Inst.PointOfInstantiation = PointOfInstantiation;
+ Inst.Template = Template;
+ Inst.Entity = reinterpret_cast<uintptr_t>(Param);
+ Inst.TemplateArgs = TemplateArgs;
+ Inst.NumTemplateArgs = NumTemplateArgs;
+ Inst.InstantiationRange = InstantiationRange;
+ SemaRef.InNonInstantiationSFINAEContext = false;
+ SemaRef.ActiveTemplateInstantiations.push_back(Inst);
+ }
}
Sema::InstantiatingTemplate::
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index bbf8f50..cce0b0d 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -2446,7 +2446,6 @@
(void) FunTmpl;
ActiveInst.Kind = ActiveInstType::TemplateInstantiation;
ActiveInst.Entity = reinterpret_cast<uintptr_t>(New);
- --SemaRef.NonInstantiationEntries;
}
}
diff --git a/test/SemaTemplate/instantiation-depth-defarg.cpp b/test/SemaTemplate/instantiation-depth-defarg.cpp
new file mode 100644
index 0000000..d66c71b
--- /dev/null
+++ b/test/SemaTemplate/instantiation-depth-defarg.cpp
@@ -0,0 +1,28 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -ftemplate-depth 512 -ftemplate-backtrace-limit 4 %s
+
+template<int N> struct S {
+ typedef typename S<N-1>::type type;
+ static int f(int n = S<N-1>::f()); // \
+// expected-error{{recursive template instantiation exceeded maximum depth of 512}} \
+// expected-note 3 {{instantiation of default function argument}} \
+// expected-note {{skipping 509 contexts in backtrace}} \
+// expected-note {{use -ftemplate-depth=N to increase recursive template instantiation depth}}
+
+};
+template<> struct S<0> {
+ typedef int type;
+};
+
+// Incrementally instantiate up to S<2048>.
+template struct S<256>;
+template struct S<512>;
+template struct S<768>;
+template struct S<1024>;
+template struct S<1280>;
+template struct S<1536>;
+template struct S<1792>;
+template struct S<2048>;
+
+// Check that we actually bail out when we hit the instantiation depth limit for
+// the default arguments.
+void g() { S<2048>::f(); } // expected-note {{required here}}
diff --git a/test/SemaTemplate/instantiation-depth-subst-2.cpp b/test/SemaTemplate/instantiation-depth-subst-2.cpp
new file mode 100644
index 0000000..a29d6b5
--- /dev/null
+++ b/test/SemaTemplate/instantiation-depth-subst-2.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -verify %s -ftemplate-depth 2
+
+template<int N> struct S { };
+// FIXME: We produce the same 'instantiation depth' error here many times
+// (2^(depth+1) in total), due to additional lookups performed as part of
+// error recovery in DiagnoseTwoPhaseOperatorLookup.
+template<typename T> S<T() + T()> operator+(T, T); // expected-error 8{{}} expected-note 10{{}}
+S<0> s;
+int k = s + s; // expected-error {{invalid operands to binary expression}}
diff --git a/test/SemaTemplate/instantiation-depth-subst.cpp b/test/SemaTemplate/instantiation-depth-subst.cpp
new file mode 100644
index 0000000..58e6374
--- /dev/null
+++ b/test/SemaTemplate/instantiation-depth-subst.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -std=c++11 -verify %s -ftemplate-depth 2
+
+// PR9793
+template<typename T> auto f(T t) -> decltype(f(t)); // \
+// expected-error {{recursive template instantiation exceeded maximum depth of 2}} \
+// expected-note 3 {{while substituting}} \
+// expected-note {{candidate}}
+
+int k = f(0); // expected-error {{no matching function for call to 'f'}}
