d: Add support for compiling without libphobos library.

Merges upstream dmd 3b3dca8be

Reviewed-on: https://github.com/dlang/dmd/pull/9678

gcc/d/ChangeLog:

2019-04-23  Iain Buclaw  <ibuclaw@gdcproject.org>

	* d-builtins.cc (d_init_versions): Add D_BetterC, D_ModuleInfo,
	D_Exceptions, D_TypeInfo as predefined version conditions.
	* d-codegen.cc (build_bounds_condition): Generate trap if D asserts
	are turned off.
	* d-frontend.cc (getTypeInfoType): Add error when -fno-rtti is set.
	* d-lang.cc (d_init_options): Initialize new front-end options.
	(d_handle_option): Handle -fdruntime, -fexceptions, and -frtti.
	(d_post_options): Turn off D runtime features if -fno-druntime is set.
	* d-spec.cc (lang_specific_driver): Handle -fdruntime.
	* d-tree.h (have_typeinfo_p): Add prototype.
	(build_typeinfo): Update prototype.
	* decl.cc (DeclVisitor::visit(StructDeclaration)): Create typeinfo
	only if TypeInfo exists.
	(DeclVisitor::visit(ClassDeclaration)): Likewise.
	(DeclVisitor::visit(InterfaceDeclaration)): Likewise.
	(DeclVisitor::visit(EnumDeclaration)): Likewise.
	* expr.cc: Update all calls to build_typeinfo.
	* gdc.texi (Runtime Options): Document -fdruntime and -frtti.
	* lang.opt: Add -fdruntime and -frtti.
	* modules.cc (build_module_tree): Create module info only if
	ModuleInfo exists.
	* toir.cc (IRVisitor::visit(ThrowStatement)): Update test for
	-fno-exceptions.
	* typeinfo.cc (create_tinfo_types): Build internal typeinfo classes
	only if Object exists.
	(have_typeinfo_p): New function.
	(class TypeInfoVisitor): Update all calls to build_typeinfo.
	(build_typeinfo): Add error when -fno-rtti is set.

gcc/testsuite/ChangeLog:

2019-04-23  Iain Buclaw  <ibuclaw@gdcproject.org>

	* gdc.test/fail_compilation/fail2456.d: New test.
	* gdc.test/fail_compilation/test18312.d: New test.
	* gdc.test/gdc-test.exp (gdc-convert-args): Handle -betterC.

From-SVN: r270518

14 files changed, 118 insertions, 104 deletions

diff --git a/gcc/d/dmd/MERGE b/gcc/d/dmd/MERGE
index c360fe5..7424576 100644
--- a/gcc/d/dmd/MERGE
+++ b/gcc/d/dmd/MERGE
@@ -1,4 +1,4 @@
-065fbd452f2aa498fc3a554be48a5495bd98aa14
+3b3dca8be201b443f17621cd29cf614007b5c75e
 
 The first line of this file holds the git revision number of the last
 merge done from the dlang/dmd repository.
diff --git a/gcc/d/dmd/clone.c b/gcc/d/dmd/clone.c
index 888cba5..d9a9055 100644
--- a/gcc/d/dmd/clone.c
+++ b/gcc/d/dmd/clone.c
@@ -839,7 +839,7 @@ FuncDeclaration *buildPostBlit(StructDeclaration *sd, Scope *sc)
         }
         else
         {
-            // _ArrayPostblit((cast(S*)this.v.ptr)[0 .. n])
+            // __ArrayPostblit((cast(S*)this.v.ptr)[0 .. n])
 
             uinteger_t n = 1;
             while (tv->ty == Tsarray)
@@ -865,7 +865,7 @@ FuncDeclaration *buildPostBlit(StructDeclaration *sd, Scope *sc)
             ((SliceExp *)ex)->upperIsInBounds = true;
             ((SliceExp *)ex)->lowerIsLessThanUpper = true;
 
-            ex = new CallExp(loc, new IdentifierExp(loc, Id::_ArrayPostblit), ex);
+            ex = new CallExp(loc, new IdentifierExp(loc, Id::__ArrayPostblit), ex);
         }
         a->push(new ExpStatement(loc, ex)); // combine in forward order
 
@@ -896,7 +896,7 @@ FuncDeclaration *buildPostBlit(StructDeclaration *sd, Scope *sc)
         }
         else
         {
-            // _ArrayDtor((cast(S*)this.v.ptr)[0 .. n])
+            // __ArrayDtor((cast(S*)this.v.ptr)[0 .. n])
 
             uinteger_t n = 1;
             while (tv->ty == Tsarray)
@@ -922,7 +922,7 @@ FuncDeclaration *buildPostBlit(StructDeclaration *sd, Scope *sc)
             ((SliceExp *)ex)->upperIsInBounds = true;
             ((SliceExp *)ex)->lowerIsLessThanUpper = true;
 
-            ex = new CallExp(loc, new IdentifierExp(loc, Id::_ArrayDtor), ex);
+            ex = new CallExp(loc, new IdentifierExp(loc, Id::__ArrayDtor), ex);
         }
         a->push(new OnScopeStatement(loc, TOKon_scope_failure, new ExpStatement(loc, ex)));
     }
@@ -1047,7 +1047,7 @@ FuncDeclaration *buildDtor(AggregateDeclaration *ad, Scope *sc)
         }
         else
         {
-            // _ArrayDtor((cast(S*)this.v.ptr)[0 .. n])
+            // __ArrayDtor((cast(S*)this.v.ptr)[0 .. n])
 
             uinteger_t n = 1;
             while (tv->ty == Tsarray)
@@ -1073,7 +1073,7 @@ FuncDeclaration *buildDtor(AggregateDeclaration *ad, Scope *sc)
             ((SliceExp *)ex)->upperIsInBounds = true;
             ((SliceExp *)ex)->lowerIsLessThanUpper = true;
 
-            ex = new CallExp(loc, new IdentifierExp(loc, Id::_ArrayDtor), ex);
+            ex = new CallExp(loc, new IdentifierExp(loc, Id::__ArrayDtor), ex);
         }
         e = Expression::combine(ex, e); // combine in reverse order
     }
diff --git a/gcc/d/dmd/dcast.c b/gcc/d/dmd/dcast.c
index 2fa762c..a3df701 100644
--- a/gcc/d/dmd/dcast.c
+++ b/gcc/d/dmd/dcast.c
@@ -131,7 +131,7 @@ Expression *implicitCastTo(Expression *e, Scope *sc, Type *t)
             visit((Expression *)e);
 
             Type *tb = result->type->toBasetype();
-            if (tb->ty == Tarray)
+            if (tb->ty == Tarray && global.params.useTypeInfo && Type::dtypeinfo)
                 semanticTypeInfo(sc, ((TypeDArray *)tb)->next);
         }
 
diff --git a/gcc/d/dmd/declaration.c b/gcc/d/dmd/declaration.c
index 835c6ae..d0911e2 100644
--- a/gcc/d/dmd/declaration.c
+++ b/gcc/d/dmd/declaration.c
@@ -2118,7 +2118,7 @@ Expression *VarDeclaration::callScopeDtor(Scope *)
         }
         else
         {
-            // _ArrayDtor(v[0 .. n])
+            // __ArrayDtor(v[0 .. n])
             e = new VarExp(loc, this);
 
             const d_uns64 sdsz = sd->type->size();
@@ -2133,7 +2133,7 @@ Expression *VarDeclaration::callScopeDtor(Scope *)
             // This is a hack so we can call destructors on const/immutable objects.
             e->type = sd->type->arrayOf();
 
-            e = new CallExp(loc, new IdentifierExp(loc, Id::_ArrayDtor), e);
+            e = new CallExp(loc, new IdentifierExp(loc, Id::__ArrayDtor), e);
         }
         return e;
     }
diff --git a/gcc/d/dmd/dinterpret.c b/gcc/d/dmd/dinterpret.c
index 40f3e77..acca4e8 100644
--- a/gcc/d/dmd/dinterpret.c
+++ b/gcc/d/dmd/dinterpret.c
@@ -4633,8 +4633,8 @@ public:
             fd = ((VarExp *)ecall)->var->isFuncDeclaration();
             assert(fd);
 
-            if (fd->ident == Id::_ArrayPostblit ||
-                fd->ident == Id::_ArrayDtor)
+            if (fd->ident == Id::__ArrayPostblit ||
+                fd->ident == Id::__ArrayDtor)
             {
                 assert(e->arguments->dim == 1);
                 Expression *ea = (*e->arguments)[0];
@@ -4654,7 +4654,7 @@ public:
                 if (CTFEExp::isCantExp(result))
                     return;
 
-                if (fd->ident == Id::_ArrayPostblit)
+                if (fd->ident == Id::__ArrayPostblit)
                     result = evaluatePostblit(istate, result);
                 else
                     result = evaluateDtor(istate, result);
diff --git a/gcc/d/dmd/dmodule.c b/gcc/d/dmd/dmodule.c
index 07e4712..1f6fd9f 100644
--- a/gcc/d/dmd/dmodule.c
+++ b/gcc/d/dmd/dmodule.c
@@ -575,69 +575,6 @@ Module *Module::parse()
             error("has non-identifier characters in filename, use module declaration instead");
     }
 
-    // Add internal used functions in 'object' module members.
-    if (!parent && ident == Id::object)
-    {
-        static const utf8_t code_ArrayEq[] =
-            "bool _ArrayEq(T1, T2)(T1[] a, T2[] b) {\n"
-            " if (a.length != b.length) return false;\n"
-            " foreach (size_t i; 0 .. a.length) { if (a[i] != b[i]) return false; }\n"
-            " return true; }\n";
-
-        static const utf8_t code_ArrayPostblit[] =
-            "void _ArrayPostblit(T)(T[] a) { foreach (ref T e; a) e.__xpostblit(); }\n";
-
-        static const utf8_t code_ArrayDtor[] =
-            "void _ArrayDtor(T)(T[] a) { foreach_reverse (ref T e; a) e.__xdtor(); }\n";
-
-        static const utf8_t code_xopEquals[] =
-            "bool _xopEquals(in void*, in void*) { throw new Error(\"TypeInfo.equals is not implemented\"); }\n";
-
-        static const utf8_t code_xopCmp[] =
-            "bool _xopCmp(in void*, in void*) { throw new Error(\"TypeInfo.compare is not implemented\"); }\n";
-
-        Identifier *arreq = Id::_ArrayEq;
-        Identifier *xopeq = Identifier::idPool("_xopEquals");
-        Identifier *xopcmp = Identifier::idPool("_xopCmp");
-        for (size_t i = 0; i < members->dim; i++)
-        {
-            Dsymbol *sx = (*members)[i];
-            if (!sx) continue;
-            if (arreq && sx->ident == arreq) arreq = NULL;
-            if (xopeq && sx->ident == xopeq) xopeq = NULL;
-            if (xopcmp && sx->ident == xopcmp) xopcmp = NULL;
-        }
-
-        if (arreq)
-        {
-            Parser p(loc, this, code_ArrayEq, strlen((const char *)code_ArrayEq), 0);
-            p.nextToken();
-            members->append(p.parseDeclDefs(0));
-        }
-        {
-            Parser p(loc, this, code_ArrayPostblit, strlen((const char *)code_ArrayPostblit), 0);
-            p.nextToken();
-            members->append(p.parseDeclDefs(0));
-        }
-        {
-            Parser p(loc, this, code_ArrayDtor, strlen((const char *)code_ArrayDtor), 0);
-            p.nextToken();
-            members->append(p.parseDeclDefs(0));
-        }
-        if (xopeq)
-        {
-            Parser p(loc, this, code_xopEquals, strlen((const char *)code_xopEquals), 0);
-            p.nextToken();
-            members->append(p.parseDeclDefs(0));
-        }
-        if (xopcmp)
-        {
-            Parser p(loc, this, code_xopCmp, strlen((const char *)code_xopCmp), 0);
-            p.nextToken();
-            members->append(p.parseDeclDefs(0));
-        }
-    }
-
     // Insert module into the symbol table
     Dsymbol *s = this;
     if (isPackageFile)
diff --git a/gcc/d/dmd/dstruct.c b/gcc/d/dmd/dstruct.c
index d35b005..1338e1f 100644
--- a/gcc/d/dmd/dstruct.c
+++ b/gcc/d/dmd/dstruct.c
@@ -23,7 +23,7 @@
 #include "template.h"
 #include "tokens.h"
 
-Type *getTypeInfoType(Type *t, Scope *sc);
+Type *getTypeInfoType(Loc loc, Type *t, Scope *sc);
 TypeTuple *toArgTypes(Type *t);
 void unSpeculative(Scope *sc, RootObject *o);
 bool MODimplicitConv(MOD modfrom, MOD modto);
@@ -101,7 +101,7 @@ void semanticTypeInfo(Scope *sc, Type *t)
             {
                 Scope scx;
                 scx._module = sd->getModule();
-                getTypeInfoType(t, &scx);
+                getTypeInfoType(sd->loc, t, &scx);
                 sd->requestTypeInfo = true;
             }
             else if (!sc->minst)
@@ -111,7 +111,7 @@ void semanticTypeInfo(Scope *sc, Type *t)
             }
             else
             {
-                getTypeInfoType(t, sc);
+                getTypeInfoType(sd->loc, t, sc);
                 sd->requestTypeInfo = true;
 
                 // Bugzilla 15149, if the typeid operand type comes from a
@@ -1165,9 +1165,12 @@ void StructDeclaration::semantic(Scope *sc)
     buildOpAssign(this, sc2);
     buildOpEquals(this, sc2);
 
-    xeq = buildXopEquals(this, sc2);
-    xcmp = buildXopCmp(this, sc2);
-    xhash = buildXtoHash(this, sc2);
+    if (global.params.useTypeInfo && Type::dtypeinfo)  // these functions are used for TypeInfo
+    {
+        xeq = buildXopEquals(this, sc2);
+        xcmp = buildXopCmp(this, sc2);
+        xhash = buildXtoHash(this, sc2);
+    }
 
     inv = buildInv(this, sc2);
 
diff --git a/gcc/d/dmd/expressionsem.c b/gcc/d/dmd/expressionsem.c
index a88ff88..19b7ccb 100644
--- a/gcc/d/dmd/expressionsem.c
+++ b/gcc/d/dmd/expressionsem.c
@@ -46,7 +46,7 @@ bool checkFrameAccess(Loc loc, Scope *sc, AggregateDeclaration *ad, size_t istar
 bool symbolIsVisible(Module *mod, Dsymbol *s);
 VarDeclaration *copyToTemp(StorageClass stc, const char *name, Expression *e);
 Expression *extractSideEffect(Scope *sc, const char *name, Expression **e0, Expression *e, bool alwaysCopy = false);
-Type *getTypeInfoType(Type *t, Scope *sc);
+Type *getTypeInfoType(Loc loc, Type *t, Scope *sc);
 bool MODimplicitConv(MOD modfrom, MOD modto);
 MATCH MODmethodConv(MOD modfrom, MOD modto);
 void MODMatchToBuffer(OutBuffer *buf, unsigned char lhsMod, unsigned char rhsMod);
@@ -713,7 +713,8 @@ public:
             return setError();
         }
 
-        semanticTypeInfo(sc, e->type);
+        if (global.params.useTypeInfo && Type::dtypeinfo)
+            semanticTypeInfo(sc, e->type);
 
         result = e;
     }
@@ -1819,7 +1820,7 @@ public:
         {
             // Handle this in the glue layer
             e = new TypeidExp(exp->loc, ta);
-            e->type = getTypeInfoType(ta, sc);
+            e->type = getTypeInfoType(exp->loc, ta, sc);
 
             semanticTypeInfo(sc, ta);
 
diff --git a/gcc/d/dmd/func.c b/gcc/d/dmd/func.c
index afba82a..568decc 100644
--- a/gcc/d/dmd/func.c
+++ b/gcc/d/dmd/func.c
@@ -246,6 +246,15 @@ public:
             s->finalbody && (des = s->finalbody->isDtorExpStatement()) != NULL &&
             fd->nrvo_var == des->var)
         {
+            if (!(global.params.useExceptions && ClassDeclaration::throwable))
+            {
+                /* Don't need to call destructor at all, since it is nrvo
+                 */
+                replaceCurrent(s->_body);
+                s->_body->accept(this);
+                return;
+            }
+
             /* Normally local variable dtors are called regardless exceptions.
              * But for nrvo_var, its dtor should be called only when exception is thrown.
              *
@@ -1325,6 +1334,16 @@ static void buildEnsureRequire(FuncDeclaration *fdx)
     }
 }
 
+/* Determine if function should add `return 0;`
+ */
+static bool addReturn0(FuncDeclaration *funcdecl)
+{
+    TypeFunction *f = (TypeFunction *)funcdecl->type;
+
+    return f->next->ty == Tvoid &&
+        (funcdecl->isMain() || (global.params.betterC && funcdecl->isCMain()));
+}
+
 // Do the semantic analysis on the internals of the function.
 
 void FuncDeclaration::semantic3(Scope *sc)
@@ -1708,7 +1727,10 @@ void FuncDeclaration::semantic3(Scope *sc)
                     Expression *exp = (*returns)[i]->exp;
                     if (exp->op == TOKvar && ((VarExp *)exp)->var == vresult)
                     {
-                        exp->type = f->next;
+                        if (addReturn0(this))
+                            exp->type = Type::tint32;
+                        else
+                            exp->type = f->next;
                         // Remove `return vresult;` from returns
                         returns->remove(i);
                         continue;
@@ -1901,7 +1923,7 @@ void FuncDeclaration::semantic3(Scope *sc)
 
             if (returns)
             {
-                bool implicit0 = (f->next->ty == Tvoid && isMain());
+                bool implicit0 = addReturn0(this);
                 Type *tret = implicit0 ? Type::tint32 : f->next;
                 assert(tret->ty != Tvoid);
                 if (vresult || returnLabel)
@@ -2123,7 +2145,7 @@ void FuncDeclaration::semantic3(Scope *sc)
                     a->push(s);
                 }
             }
-            if (isMain() && f->next->ty == Tvoid)
+            if (addReturn0(this))
             {
                 // Add a return 0; statement
                 Statement *s = new ReturnStatement(Loc(), new IntegerExp(0));
diff --git a/gcc/d/dmd/globals.h b/gcc/d/dmd/globals.h
index e2d42c7..1094679 100644
--- a/gcc/d/dmd/globals.h
+++ b/gcc/d/dmd/globals.h
@@ -36,6 +36,14 @@ enum BOUNDSCHECK
     BOUNDSCHECKsafeonly // do bounds checking only in @safe functions
 };
 
+typedef unsigned char CHECKACTION;
+enum
+{
+    CHECKACTION_D,        // call D assert on failure
+    CHECKACTION_C,        // call C assert on failure
+    CHECKACTION_halt      // cause program halt on failure
+};
+
 enum CPU
 {
     x87,
@@ -116,6 +124,9 @@ struct Param
     bool nofloat;       // code should not pull in floating point support
     bool ignoreUnsupportedPragmas;      // rather than error on them
     bool enforcePropertySyntax;
+    bool useModuleInfo; // generate runtime module information
+    bool useTypeInfo;   // generate runtime type information
+    bool useExceptions; // support exception handling
     bool betterC;       // be a "better C" compiler; no dependency on D runtime
     bool addMain;       // add a default main() function
     bool allInst;       // generate code for all template instantiations
@@ -126,7 +137,9 @@ struct Param
     bool showGaggedErrors;  // print gagged errors anyway
 
     CPU cpu;                // CPU instruction set to target
-    BOUNDSCHECK useArrayBounds;
+
+    BOUNDSCHECK useArrayBounds;    // when to generate code for array bounds checks
+    CHECKACTION checkAction;       // action to take when bounds, asserts or switch defaults are violated
 
     const char *argv0;    // program name
     Array<const char *> *modFileAliasStrings; // array of char*'s of -I module filename alias strings
diff --git a/gcc/d/dmd/idgen.c b/gcc/d/dmd/idgen.c
index e750048..dc0ecd1 100644
--- a/gcc/d/dmd/idgen.c
+++ b/gcc/d/dmd/idgen.c
@@ -264,9 +264,9 @@ Msgtable msgtable[] =
     { "monitorexit", "_d_monitorexit" },
     { "criticalenter", "_d_criticalenter" },
     { "criticalexit", "_d_criticalexit" },
-    { "_ArrayEq", NULL },
-    { "_ArrayPostblit", NULL },
-    { "_ArrayDtor", NULL },
+    { "__ArrayEq", NULL },
+    { "__ArrayPostblit", NULL },
+    { "__ArrayDtor", NULL },
     { "dup", NULL },
     { "_aaApply", NULL },
     { "_aaApply2", NULL },
diff --git a/gcc/d/dmd/opover.c b/gcc/d/dmd/opover.c
index 453ba65..b3ea6cf 100644
--- a/gcc/d/dmd/opover.c
+++ b/gcc/d/dmd/opover.c
@@ -900,7 +900,9 @@ Expression *op_overload(Expression *e, Scope *sc)
             if (t->ty != Tstruct)
                 return false;
 
-            semanticTypeInfo(sc, t);
+            if (global.params.useTypeInfo && Type::dtypeinfo)
+                semanticTypeInfo(sc, t);
+
             return ((TypeStruct *)t)->sym->hasIdentityEquals;
         }
 
@@ -919,9 +921,9 @@ Expression *op_overload(Expression *e, Scope *sc)
                 if (needsDirectEq(t1, t2, sc))
                 {
                     /* Rewrite as:
-                     *      _ArrayEq(e1, e2)
+                     *      __ArrayEq(e1, e2)
                      */
-                    Expression *eeq = new IdentifierExp(e->loc, Id::_ArrayEq);
+                    Expression *eeq = new IdentifierExp(e->loc, Id::__ArrayEq);
                     result = new CallExp(e->loc, eeq, e->e1, e->e2);
                     if (e->op == TOKnotequal)
                         result = new NotExp(e->loc, result);
diff --git a/gcc/d/dmd/parse.c b/gcc/d/dmd/parse.c
index 3afdbc2..9da58af 100644
--- a/gcc/d/dmd/parse.c
+++ b/gcc/d/dmd/parse.c
@@ -70,7 +70,6 @@ Parser::Parser(Loc loc, Module *module, const utf8_t *base, size_t length, bool
     //printf("Parser::Parser()\n");
     scanloc = loc;
 
-#ifndef IN_GCC
     if (loc.filename)
     {
         /* Create a pseudo-filename for the mixin string, as it may not even exist
@@ -80,7 +79,6 @@ Parser::Parser(Loc loc, Module *module, const utf8_t *base, size_t length, bool
         sprintf(filename, "%s-mixin-%d", loc.filename, (int)loc.linnum);
         scanloc.filename = filename;
     }
-#endif
 
     mod = module;
     md = NULL;
diff --git a/gcc/d/dmd/statementsem.c b/gcc/d/dmd/statementsem.c
index f694fb1..64cc42d 100644
--- a/gcc/d/dmd/statementsem.c
+++ b/gcc/d/dmd/statementsem.c
@@ -2073,8 +2073,19 @@ public:
             CompoundStatement *cs;
             Statement *s;
 
-            if (global.params.useSwitchError)
-                s = new SwitchErrorStatement(ss->loc);
+            if (global.params.useSwitchError &&
+                global.params.checkAction != CHECKACTION_halt)
+            {
+                if (global.params.checkAction == CHECKACTION_C)
+                {
+                    /* Rewrite as an assert(0) and let e2ir generate
+                     * the call to the C assert failure function
+                     */
+                    s = new ExpStatement(ss->loc, new AssertExp(ss->loc, new IntegerExp(ss->loc, 0, Type::tint32)));
+                }
+                else
+                    s = new SwitchErrorStatement(ss->loc);
+            }
             else
                 s = new ExpStatement(ss->loc, new HaltExp(ss->loc));
 
@@ -3118,6 +3129,18 @@ public:
 
     void visit(TryCatchStatement *tcs)
     {
+        if (!global.params.useExceptions)
+        {
+            tcs->error("Cannot use try-catch statements with -betterC");
+            return setError();
+        }
+
+        if (!ClassDeclaration::throwable)
+        {
+            tcs->error("Cannot use try-catch statements because `object.Throwable` was not declared");
+            return setError();
+        }
+
         unsigned flags = 0;
         const unsigned FLAGcpp = 1;
         const unsigned FLAGd = 2;
@@ -3227,7 +3250,14 @@ public:
             return;
         }
 
-        if (blockExit(tfs->_body, sc->func, false) == BEfallthru)
+        int blockexit = blockExit(tfs->_body, sc->func, false);
+
+        // if not worrying about exceptions
+        if (!(global.params.useExceptions && ClassDeclaration::throwable))
+            blockexit &= ~BEthrow;            // don't worry about paths that otherwise may throw
+
+        // Don't care about paths that halt, either
+        if ((blockexit & ~BEhalt) == BEfallthru)
         {
             result = new CompoundStatement(tfs->loc, tfs->_body, tfs->finalbody);
             return;
@@ -3237,7 +3267,6 @@ public:
 
     void visit(OnScopeStatement *oss)
     {
-#ifndef IN_GCC
         if (oss->tok != TOKon_scope_exit)
         {
             // scope(success) and scope(failure) are rewritten to try-catch(-finally) statement,
@@ -3255,7 +3284,6 @@ public:
                 return setError();
             }
         }
-#endif
 
         sc = sc->push();
         sc->tf = NULL;
@@ -3281,6 +3309,18 @@ public:
     {
         //printf("ThrowStatement::semantic()\n");
 
+        if (!global.params.useExceptions)
+        {
+            ts->error("Cannot use `throw` statements with -betterC");
+            return setError();
+        }
+
+        if (!ClassDeclaration::throwable)
+        {
+            ts->error("Cannot use `throw` statements because `object.Throwable` was not declared");
+            return setError();
+        }
+
         FuncDeclaration *fd = sc->parent->isFuncDeclaration();
         fd->hasReturnExp |= 2;
 
@@ -3463,7 +3503,6 @@ void semantic(Catch *c, Scope *sc)
 {
     //printf("Catch::semantic(%s)\n", ident->toChars());
 
-#ifndef IN_GCC
     if (sc->os && sc->os->tok != TOKon_scope_failure)
     {
         // If enclosing is scope(success) or scope(exit), this will be placed in finally block.
@@ -3481,7 +3520,6 @@ void semantic(Catch *c, Scope *sc)
         error(c->loc, "cannot put catch statement inside finally block");
         c->errors = true;
     }
-#endif
 
     ScopeDsymbol *sym = new ScopeDsymbol();
     sym->parent = sc->scopesym;