https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91479
Bug ID: 91479
Summary: Template deductions fails for static template member
with default template parameter when inside template
class
Product: gcc
Version: 10.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: dmatthews at utexas dot edu
Target Milestone: ---
This minimal program:
template <class T> struct foo
{
template <typename U, typename=void>
static void bar(const U&) {}
static void bar(int x) { bar<int>(x); }
};
causes the following error with gcc 9.x and 10.0, but not 8.3 or before
(clang/icpc also compile correctly):
<source>: In static member function 'static void foo<T>::bar(int)':
<source>:6:40: error: no matching function for call to 'foo<T>::bar<int>(int&)'
6 | static void bar(int x) { bar<int>(x); }
| ^
<source>:4:17: note: candidate: 'template<class T> template<class U, class>
static void foo<T>::bar(const U&)'
4 | static void bar(const U&) {}
| ^~~
<source>:4:17: note: template argument deduction/substitution failed:
<source>:6:40: note: mismatched types 'const U' and 'int'
6 | static void bar(int x) { bar<int>(x); }
|
Output of "gcc -v":
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-snapshot/bin/g++
Target: x86_64-linux-gnu
Configured with: ../gcc-trunk-20190817/configure
--prefix=/opt/compiler-explorer/gcc-build/staging --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu --disable-bootstrap
--enable-multiarch --with-abi=m64 --with-multilib-list=m32,m64,mx32
--enable-multilib --enable-clocale=gnu --enable-languages=c,c++,fortran,ada
--enable-ld=yes --enable-gold=yes --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --enable-linker-build-id --enable-lto
--enable-plugins --enable-threads=posix
--with-pkgversion=Compiler-Explorer-Build
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 10.0.0 20190816 (experimental) (Compiler-Explorer-Build)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' './output.s'
'-masm=intel' '-S' '-v' '-E' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
/opt/compiler-explorer/gcc-trunk-20190817/bin/../libexec/gcc/x86_64-linux-gnu/10.0.0/cc1plus
-E -quiet -v -imultiarch x86_64-linux-gnu -iprefix
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/
-D_GNU_SOURCE <source> -o ./output.s -masm=intel -mtune=generic -march=x86-64
-fdiagnostics-color=always -g -fworking-directory
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../x86_64-linux-gnu/include"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../include/c++/10.0.0"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../include/c++/10.0.0/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../include/c++/10.0.0/backward"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/10.0.0/include"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/10.0.0/include-fixed"
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../include/c++/10.0.0
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../include/c++/10.0.0/x86_64-linux-gnu
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../include/c++/10.0.0/backward
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/include
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/include-fixed
/usr/local/include
/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/../../include
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
COMPILER_PATH=/opt/compiler-explorer/gcc-trunk-20190817/bin/../libexec/gcc/x86_64-linux-gnu/10.0.0/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../libexec/gcc/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../libexec/gcc/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../x86_64-linux-gnu/bin/
LIBRARY_PATH=/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../lib64/:/lib/x86_64-linux-gnu/:/lib/../lib64/:/usr/lib/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../../x86_64-linux-gnu/lib/:/opt/compiler-explorer/gcc-trunk-20190817/bin/../lib/gcc/x86_64-linux-gnu/10.0.0/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' './output.s'
'-masm=intel' '-S' '-v' '-E' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
