internal compiler error: in tsubst_copy

[Joris Van Remoortere]

lsb_release -rd:
Description: Ubuntu 12.04 LTS
Release: 12.04

gcc -v:
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.7/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.7.0-7ubuntu3' --with-bugurl=file:///usr/share/doc/gcc-4.7/README.Bugs --enable-languages=c,c++,go,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.7 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.7 --libdir=/usr/lib --enable-nls --disable-bootstrap --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --enable-objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.7.0 (Ubuntu/Linaro 4.7.0-7ubuntu3)

Command:
g++ -DTEST_OUTPUT_DIR="/tmp/" -g -Wno-type-limits -Werror -DDEBUG -Wno-parentheses -Wold-style-cast -Wall -Wextra -std=c++0x -I/usr/include/ -I/usr/lib/gcc/x86_64-linux-gnu/4.6.1/include-fixed/ -I/usr/lib/gcc/x86_64-linux-gnu/4.6.1/include/ -c -I/home/XXX/projects/src -I/home/XXX/projects/out/debug -o/home/XXX/projects/out/debug/exp/joris/gcc/inline_cons.o -D'SRC_ROOT="/home/XXX/projects/src"' /home/XXX/projects/src/exp/joris/gcc/inline_cons.cc
exp/joris/gcc/inline_cons.cc:
/home/XXX/projects/src/exp/joris/gcc/inline_cons.cc: In constructor ‘TFoo<TVal>::TFoo(const std::function<bool(const TVal&, const TVal&)>&) [with TVal = int]’:
/home/XXX/projects/src/exp/joris/gcc/inline_cons.cc:12:13: internal compiler error: in tsubst_copy, at cp/pt.c:12113

Source:

#include <functional>
template <typename TVal>
class TFoo {
  public:
  TFoo(const std::function<bool (const TVal &, const TVal &)> &func = [](const TVal &lhs, const TVal &rhs){return lhs < rhs;}) {}
};
int main() {
  TFoo<int> foo;
}

[Richard Eames (naddiseo)]

$ g++ -std=c++0x -o test.bin testcase.cpp
test.cpp: In member function ‘void Foo::dostuff(T, U) [with T = Bar, U = bool(Arg*)]’:
test.cpp:21:17: internal compiler error: in tsubst_copy, at cp/pt.c:11333
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-4.6/README.Bugs> for instructions.

$ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.6.1/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.6.1-9ubuntu3' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr --program-suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3)

[Richard Eames (naddiseo)]

Created attachment 26304
Testcase

[Richard Eames (naddiseo)]

Tested in 4.7.0, fails too.

$ /usr/lib/gcc-snapshot/bin/g++ -std=c++0x -o test.bin testcase.cpp
testcase.cpp: In member function 'void Foo::dostuff(T, U) [with T = Bar; U = bool(Arg*)]':
testcase.cpp:21:17: internal compiler error: in tsubst_copy, at cp/pt.c:11748

$ /usr/lib/gcc-snapshot/bin/g++ -v
Using built-in specs.
COLLECT_GCC=/usr/lib/gcc-snapshot/bin/g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc-snapshot/libexec/gcc/x86_64-linux-gnu/4.7.0/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 20111010-0ubuntu1' --with-bugurl=file:///usr/share/doc/gcc-snapshot/README.Bugs --enable-languages=c,ada,c++,java,fortran,objc,obj-c++,go --prefix=/usr/lib/gcc-snapshot --enable-shared --enable-linker-build-id --with-system-zlib --disable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.7-snap/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.7-snap --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.7-snap --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=yes --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.7.0 20111010 (experimental) [trunk revision 179769] (Ubuntu/Linaro 20111010-0ubuntu1)

[Rguenth (rguenth)]

Confirmed. Not sure if the testcase is valid or not.

[Redi (redi)]

It's not valid, you can't pass a function type by value

[Richard Eames (naddiseo)]

I've reduced the testcase further. It appears to be a problem with templates. The reason I was passing a function type in the template was because std::function<bool(Arg*)> wouldn't work for me. If I take out the first parameter so that it's just the function pointer, then std::function works with the lambda as a default argument, but as soon as the function is templated I get the IRC.

[Richard Eames (naddiseo)]

Created attachment 26309
Reduced test case

[Redi (redi)]

Further reduced

struct function
{
  template<typename T>
    function(T) { }
};

class Foo {
public:
  template<typename>
    void dostuff(function callback = []() { }) { }
};

int main() {
  Foo foo;
  foo.dostuff<int>();
}

[Matthias Klose (doko)]

confirmed for 4.6, 4.7 and snapshot

[Paolo-carlini (paolo-carlini)]

This is fixed in mainline. I'm adding the reduced testcase and closing the issue.

[Paolo-carlini (paolo-carlini)]

It's in fact a Dup.

*** This bug has been marked as a duplicate of bug 55223 ***