[Bug c++/97591] Segmentation fault by non-type template parameters
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97591 --- Comment #4 from Vladimir Meremyanin --- Maybe but in the #95291 crash occurs when access member, and here when operator() is called. So probably both issues have a single cause.
[Bug c++/97591] Segmentation fault by non-type template parameters
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97591 Marek Polacek changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED CC||mpolacek at gcc dot gnu.org Resolution|--- |DUPLICATE --- Comment #3 from Marek Polacek --- Looks like a dup. *** This bug has been marked as a duplicate of bug 95291 ***
[Bug c++/97591] Segmentation fault by non-type template parameters
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97591
--- Comment #2 from Vladimir Meremyanin ---
Program source:
// /usr/local/Cellar/gcc/10.2.0/bin/g++-10 -std=c++20 type-level-routes.cpp
#include
#include
// FixedString from
https://www.reddit.com/r/cpp/comments/bhxx49/c20_string_literals_as_nontype_template/
template
struct FixedString {
char buf[N + 1]{};
constexpr FixedString(char const* s) {
for (unsigned i = 0; i != N; ++i) buf[i] = s[i];
}
constexpr operator char const*() const { return buf; }
};
template FixedString(char const (&)[N]) -> FixedString;
// own code
// Static url part
template
struct Slug {
static constexpr char const* path = Path;
};
// Dynamic url part
template
struct Capture {
using value_t = Value;
};
// Route
template
struct Route;
template
struct Route, Rest...> {
static std::string toString(ValueT value, auto... rest) {
return "/" + std::to_string(value) + Route::toString(rest...);
}
};
template
struct Route, Rest...> { /* <--- Path() here causes
compiler segfault */
static std::string toString(auto... rest) {
return "/" + std::string(SlugT::path) + Route::toString(rest...);
}
};
template <>
struct Route<> {
static std::string toString() {
return "";
}
};
using BlogRoot = Route< "blog" >;
using AllPosts = Route< "blog", "posts" >;
using SinglePost = Route< "blog", "posts", Capture >;
int main() {
// /blog
std::cout << "blog = " << BlogRoot::toString() << std::endl;
// /blog/posts
std::cout << "allPosts = " << AllPosts::toString() << std::endl;
// invalid path, compilation error
// std::cout << "singlePost = " << SinglePost::toString() << std::endl;
// /blog/posts/42
std::cout << "singlePost = " << SinglePost::toString(42) << std::endl;
return 0;
}
[Bug c++/97591] Segmentation fault by non-type template parameters
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97591 --- Comment #1 from Vladimir Meremyanin --- g++-10 -v Using built-in specs. COLLECT_GCC=/usr/local/Cellar/gcc/10.2.0/bin/g++-10 COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc/10.2.0/libexec/gcc/x86_64-apple-darwin19/10.2.0/lto-wrapper Target: x86_64-apple-darwin19 Configured with: ../configure --build=x86_64-apple-darwin19 --prefix=/usr/local/Cellar/gcc/10.2.0 --libdir=/usr/local/Cellar/gcc/10.2.0/lib/gcc/10 --disable-nls --enable-checking=release --enable-languages=c,c++,objc,obj-c++,fortran --program-suffix=-10 --with-gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with-mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl --with-system-zlib --with-pkgversion='Homebrew GCC 10.2.0' --with-bugurl=https://github.com/Homebrew/homebrew-core/issues --disable-multilib --with-native-system-header-dir=/usr/include --with-sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk SED=/usr/bin/sed Thread model: posix Supported LTO compression algorithms: zlib gcc version 10.2.0 (Homebrew GCC 10.2.0)
