Bug 4620 – C++ constructor and template mangling, C++ ABI patch

Created attachment 712 Demo: using Qt through native C++ interface (without compiled bindings) --- a/cppmangle.c 2010-08-11 13:28:34.000000000 +0200 +++ b/cppmangle.c 2010-08-11 13:28:34.000000000 +0200 @@ -106,14 +106,36 @@ Dsymbol *p = s->toParent(); if (p && !p->isModule()) { + TemplateInstance *ti = p->isTemplateInstance(); + if(ti) + { + char *name = ti->name->toChars(); + buf->printf("%d%s", strlen(name), name); + buf->writeByte('I'); + for (size_t j = 0; j < ti->tiargs->dim; j++) + { + Object *o = (Object *)ti->tiargs->data[j]; + Type *t = isType(o); + if (t) t->toCppMangle(buf, cms); + } + buf->writeByte('E'); + return; + } + buf->writeByte('N'); FuncDeclaration *fd = s->isFuncDeclaration(); - if (fd->isConst()) + if (fd && fd->isConst()) buf->writeByte('K'); prefix_name(buf, cms, p); - source_name(buf, s); + cms->components.push(s); + if (!strcmp(s->ident->toChars(), "__ctor")) { + buf->writeByte('C'); + buf->writeByte('1'); + } else { + source_name(buf, s); + } buf->writeByte('E'); } @@ -197,10 +219,11 @@ * z ellipsis * u <source-name> # vendor extended type */ - - if (isConst()) + if (isConst()) { + if (cms->substitute(buf, this)) + return; buf->writeByte('K'); - + } switch (ty) { case Tvoid: c = 'v'; break; @@ -320,6 +343,11 @@ void TypeStruct::toCppMangle(OutBuffer *buf, CppMangleState *cms) { + if (isConst()) + { + if ( !cms->substitute(buf, this) ) + buf->writeByte('K'); + } if (!cms->substitute(buf, sym)) cpp_mangle_name(buf, cms, sym); } --- a/expression.c 2010-08-11 13:16:54.000000000 +0200 +++ b/expression.c 2010-08-11 13:16:54.000000000 +0200 @@ -6741,6 +6741,10 @@ e = new DotTemplateExp(loc, av, td); } e = new CallExp(loc, e, arguments); + if (cf && cf->linkage != LINKd) + { //C++ constructor return void + e = new CommaExp(loc, e, new VarExp(loc, tmp)); + } #if !STRUCTTHISREF /* Constructors return a pointer to the instance */ --- a/e2ir.c 2010-08-11 11:51:32.000000000 +0200 +++ b/e2ir.c 2010-08-11 11:51:32.000000000 +0200 @@ -137,7 +137,7 @@ { Parameter *p = Parameter::getNth(tf->parameters, i - j); - if (p->storageClass & (STCout | STCref)) + if (p->storageClass & (STCout | STCref) || (p->type->ty == Tstruct && tf->linkage != LINKd)) { // Convert argument to a pointer, // use AddrExp::toElem() @@ -1733,11 +1733,18 @@ if (member) { // Call constructor ez = callfunc(loc, irs, 1, type, ez, ectype, member, member->type, NULL, arguments); + TypeFunction* tf = (TypeFunction *)(member->type); + if (tf->linkage != LINKd) + { //C++ constructor return void + ez = el_combine(ez, el_same(&ex)); + } #if STRUCTTHISREF - /* Structs return a ref, which gets automatically dereferenced. - * But we want a pointer to the instance. - */ - ez = el_una(OPaddr, TYnptr, ez); + else { + /* Structs return a ref, which gets automatically dereferenced. + * But we want a pointer to the instance. + */ + ez = el_una(OPaddr, TYnptr, ez); + } #endif }

Created attachment 713 Patch against r615

I'd really like to see something happen with this. Even if it doesn't work for everything, calling more C++ is only a good thing for D.

PING. This issue is interested for me? Can this feature be merged or this issue is invalid?

It looks like the template mangling has been superceeded by other development. Is the construct part still relevant?

Indeed the code has evolved a lot since then, and C++ interfacing is much easier in D nowadays. Closing as WONTFIX so it doesn't show up in the changelog.

(In reply to Mathias LANG from comment #5) > Indeed the code has evolved a lot since then, and C++ interfacing is much > easier in D nowadays. Closing as WONTFIX so it doesn't show up in the > changelog. Just a note: it only shows in the changelog if there is a git log message that references this bug -- all the changelog is auto-generated these days.