c++/3086: Suggested extension to a template related warning.

[whitley at bangpath dot org]

>Number:         3086
>Category:       c++
>Synopsis:       Suggested extension to a template related warning.
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Fri Jun 08 13:56:01 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     John Whitley
>Release:        gcc version 2.95.4 20010604 (Debian prerelease)
>Organization:
>Environment:
Current (as of about 7/7/2001) Debian unstable Linux i386 box
>Description:
This report also applies to the following gcc 3.0 version:
Configured with: ../src/configure -v --enable-languages=c,c++,java,f77,proto,objc --prefix=/usr --infodir=/share/info --mandir=/share/man --enable-shared --with-gnu-as --with-gnu-ld --with-system-zlib --enable-long-long --enable-nls --without-x --without-included-gettext --disable-checking --enable-threads=posix --enable-java-gc=boehm --with-cpp-install-dir=bin --enable-objc-gc i386-linux
Thread model: posix
gcc version 3.0 20010526 (Debian prerelease)

A declaration such as "stack<stack<int>>" will correctly issue the warning:
"`>>' should be `> >' in template class name"

However, the attached sample code fails to emit this very helpful warning, instead producing a rather inscrutable error (for gcc 2.95.4 -- the warning differs slightly for gcc 3.0, but appears to have the same meaning.)

The erroneous declaration (from line 37) is:
  Handle<MyPrivateData<FOO>> handle(pd);

Which produces the error message.

param_templ2.cpp: In function `int main()':
param_templ2.cpp:37: implicit declaration of function `int handle(...)'
[...]

Hopefully the attached file will be helpful in extending the above warning to cover more cases.

Thanks for the great compilers!
-- John Whitley
>How-To-Repeat:
g++ param_templ2.cpp
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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