Bug 3034 – Template instance name wrongly mangled as LName

Created attachment 384 Fix the problem (dmd 2.030) DMD wrongly mangles template instance name as LName, not TemplateInstanceName: -------------------- module test; template Temp() { struct S {} } pragma(msg, Temp!().S.mangleof); -------------------- S4test9__T4TempZ1S -------------------- In the above example, DMD mangles the template instance Temp!() to "9__T4TempZ". Note the preceding number. According to the spec, template instance name should be mangled without preceding number: -------------------- SymbolName: LName TemplateInstanceName LName: Number Name TemplateInstanceName: __T LName TemplateArgs Z -------------------- This prevents a name demangler from telling the difference between a usual identifier and template instance name. For example, a demangler can recognize "9__T4TempZ" as a valid module name, not a template instance. The proposed patch fixes mangle(Declaration *sthis) and TemplateInstance::mangle() (mangle.c).

Created attachment 387 Fix the problem (DMD 2.030) I forgot to deal with TemplateMixin. It should be mangled as LName.

The current scheme requires arbitrary lookahead to determine whether a symbol represents a template (see core.demangle.parseSymbolName, for example). If the leading Number were removed then testing for template vs. LName would basically be a matter of checking for a digit vs. underscore. I very much support the idea of eliminating the leading number for template names.

Just tested on git master and the result is "S4test__T4TempZ1S". Closing as fixed.