digitalmars.D.bugs - [Issue 3276] New: Mutual recursion broken in type templates
- d-bugmail puremagic.com (22/22) Aug 31 2009 http://d.puremagic.com/issues/show_bug.cgi?id=3276
- d-bugmail puremagic.com (24/24) May 12 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3276
- d-bugmail puremagic.com (49/49) Nov 02 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3276
- d-bugmail puremagic.com (36/36) Nov 02 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3276
- Don (4/8) Nov 03 2010 What do you mean, the broken test? It needs to pass, unless you have
- d-bugmail puremagic.com (12/12) Dec 05 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3276
http://d.puremagic.com/issues/show_bug.cgi?id=3276 Summary: Mutual recursion broken in type templates Product: D Version: 2.032 Platform: x86 OS/Version: Windows Status: NEW Severity: critical Priority: P2 Component: DMD AssignedTo: nobody puremagic.com ReportedBy: bartosz relisoft.com Created an attachment (id=442) --> (http://d.puremagic.com/issues/attachment.cgi?id=442) bug example Recursion in templates works, but mutual recursion doesn’t. I’m attaching this example—it can’t be reduced much further. Each part of it works separately, but once they start recursing into each other, I get the error: small.d(3): Error: alias small.F!(void*).StripPtr recursive alias declaration -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Aug 31 2009
http://d.puremagic.com/issues/show_bug.cgi?id=3276 Don <clugdbug yahoo.com.au> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |rejects-valid CC| |clugdbug yahoo.com.au Summary|Mutual recursion broken in |Recursion broken by alias |type templates |template parameter Reduced test case shows it doesn't involve mutual recursion (original title was "Mutual recursion broken in type templates") template Bug3276(bool B) { static if (B) alias Bug3276!(false) Bug3276; else alias double Bug3276; } template Bug3276_b(alias W) { alias W!(true) Bug3276_b; } alias Bug3276_b!(Bug3276) Bug3276_c; -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
May 12 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3276 Shin Fujishiro <rsinfu gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |rsinfu gmail.com --- The bug happens if a recursive template is instantiated via an alias: alias Bug3276 W; alias W!true w; In template.c, the following if at the line 4304 tries to get the relevant TemplateDeclaration for doing recursion: TemplateDeclaration *TemplateInstance::findTemplateDeclaration(Scope *sc) { ... TemplateInstance *ti; if (s->parent && (ti = s->parent->isTemplateInstance()) != NULL) { if ( (ti->name == id || ti->toAlias()->ident == id) // <-- the cause && ti->tempdecl) ... } Here 'this' refers to the recursive instantiation "Bug3276!(false)" and id="Bug3276" is its identifier. 'ti' is the enclosing TemplateInstance (i.e. "W!(true)"). The test sees if the identifier 'id' used in the instantiation "Bug3276!(false)" is the same as the one of enclosing 'ti'. But 'ti' was instantiated with the aliased identifier (ti->name="W"), so the first condition isn't met. Then it tests the next condition: ti->toAlias()->ident. It dives into the following code in TemplateInstance::toAlias(): if (aliasdecl) { return aliasdecl->toAlias(); } Here 'aliasdecl' is the "result" of the eponymous template "Bug3276!(true)", and it's exactly the "alias Bug3276!(false)" analyzing now. AliasDeclaration::toAlias() does the follownig check: if (inSemantic) { error("recursive alias declaration"); aliassym = new TypedefDeclaration(loc, ident, Type::terror, NULL); } Since it's in semantic, the compiler raises the error. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Nov 02 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3276 Shin Fujishiro <rsinfu gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |patch --- Patch against dmd r737. --- src/template.c +++ src/template.c -4304,11 +4304,7 TemplateDeclaration *TemplateInstance::findTemplateDeclaration(Scope *sc) if (s->parent && (ti = s->parent->isTemplateInstance()) != NULL) { - if ( - (ti->name == id || - ti->toAlias()->ident == id) - && - ti->tempdecl) + if (ti->tempdecl && ti->tempdecl->ident == id) { /* This is so that one can refer to the enclosing * template, even if it has the same name as a member Getting 'ti' for recognizing recursion is good; but the identifier should be compared with the one of a TemplateDeclaration, not the TemplateInstance. As happened in the reported bug, ti->name is not always the appropriate identifier for recursion check. The patch removes ti->toAlias() for good. TemplateInstance::toAlias() does *not* resolve alias of itself; as seen in its implementation, it actually returns the "result" of the template and makes no sense. 'id' has to be compared with ti->tempdecl->ident. The patch passed dmd, druntime and phobos tests. It couldn't pass the broken test (runnable/interpret.d) though. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Nov 02 2010
d-bugmail puremagic.com wrote:http://d.puremagic.com/issues/show_bug.cgi?id=3276 ---The patch passed dmd, druntime and phobos tests. It couldn't pass the broken test (runnable/interpret.d) though.What do you mean, the broken test? It needs to pass, unless you have modified the file from the one in svn. (It fails on Linux with -O, but that is not part of the test).
Nov 03 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3276 Walter Bright <bugzilla digitalmars.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED CC| |bugzilla digitalmars.com Resolution| |FIXED 23:00:13 PST --- http://www.dsource.org/projects/dmd/changeset/784 -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Dec 05 2010