Up to Discussions in C/C++ Café

This Question is Possibly Answered

1 "correct" answer available (4 pts) 1 "helpful" answer available (2 pts)
2 Replies Last post: Jun 23, 2009 7:36 AM by Michael_Wong  
Click to view Alexander-Vinokur's profile  
Alexander-Vinokur
4 posts since
Jun 22, 2009

Jun 22, 2009 2:22 AM

1540-0701 (S) The limit on nested template

Hi,

uname -a
AIX ilibm016 3 5 0004F43AD400

/usr/vacpp/bin/xlC_r -qversion
IBM XL C/C++ Enterprise Edition V8.0 for AIX
Version: 08.00.0000.0000

Here is some program

      • prog.cpp ---
template <int N>
int foo()
{
return (foo<N-1>() + 2);
}

template <>
int foo<0>()
{
return 0;
}

int main()
{
int value = foo<300>();
return value;
}

Compilation:

/usr/vacpp/bin/xlC_r -q64 -qwarn64 prog.cpp "prog.cpp", line 2.5: 1540-0701 (S) The limit on nested template
instantiations has been exceeded while instantiating "int foo<250>()".


============================

Question-1. Is there any compilation option or pragma that enables the
user to increase the template-related recursion deep/limit?

Question-2. Does any xlC's description contains the exact value of
that limit?

Thanks.

Alex Vinokur

Tags: aix, c++, templates
Click to view DaveyC's profile  
DaveyC
22 posts since
Jan 20, 2009
1. Jun 23, 2009 7:24 AM in response to: Alexander-Vinokur
Re: 1540-0701 (S) The limit on nested template
Works fine on the z/OS v1.10 compiler. I thought they all shared the same front end? BTW, good luck. Template meta-programming is for the hard core! Wouldn't want to support it...
Click to view Michael_Wong's profile  
Michael_Wong
19 posts since
Sep 30, 2008
2. Jun 23, 2009 7:38 AM in response to: Alexander-Vinokur
Re: 1540-0701 (S) The limit on nested template
Hi, xlC++ (AIX/Linux) V10.1 has template depth control, starting with V9. But V8 does not have that option.
-qtemplatedepth (C++ only)
Category

Template control
Pragma equivalent

None.
Purpose

Specifies the maximum number of recursively instantiated template specializations that will be processed by the compiler.
Syntax

Read syntax diagramSkip visual syntax diagram
- -q--templatedepth--=--number-------------------------------><

Defaults

-qtemplatedepth=300
Parameters

number
The maximum number of recursive template instantiations. The number can be a value between 1 and INT_MAX. If your code attempts to recursively instantiate more templates than number, compilation halts and an error message is issued. If you specify an invalid value, the default value of 300 is used.

Usage

Note that setting this option to a high value can potentially cause an out-of-memory error due to the complexity and amount of code generated.
Predefined macros

None.
Examples
To allow the following code in myprogram.cpp to be compiled successfully:

template <int n> void foo() {
foo<n-1>();
}

template void foo<0>() {}

int main() {
foo<400>();
}

Enter:

xlc++ myprogram.cpp -qtemplatedepth=400

Related information

* Using C++ templates .

Parent topic: Individual option descriptions

Provide feedback

Actions

More Like This

Bottom Banner