Deepcopy of objects doesn't work

[tanay-man]

Example:

from lpython import i32

class coord:
    def __init__(self:"coord", x:i32, y:i32):
        self.x: i32 = x 
        self.y: i32 = y

p1: coord = coord(1, 2)
p2: coord = p1

Output

Traceback (most recent call last):
  Binary file "/home/tanay/lcompilers/lpython/src/bin/lpython", in _start()
  File "./csu/../csu/libc-start.c", line 392, in __libc_start_main_impl()
  File "./csu/../sysdeps/nptl/libc_start_call_main.h", line 58, in __libc_start_call_main()
  File "/home/tanay/lcompilers/lpython/src/bin/lpython.cpp", line 2244, in ??
    err = compile_python_using_llvm(arg_file, tmp_o, runtime_library_dir,
  File "/home/tanay/lcompilers/lpython/src/bin/lpython.cpp", line 1117, in ??
    res = fe.get_llvm3(*asr, pass_manager, diagnostics, infile);
  File "/home/tanay/lcompilers/lpython/src/lpython/python_evaluator.cpp", line 450, in LCompilers::PythonCompiler::get_llvm3(LCompilers::ASR::TranslationUnit_t&, LCompilers::PassManager&, LCompilers::diag::Diagnostics&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)
    run_fn, global_underscore_name, infile);
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 10168, in LCompilers::asr_to_llvm(LCompilers::ASR::TranslationUnit_t&, LCompilers::diag::Diagnostics&, llvm::LLVMContext&, Allocator&, LCompilers::PassManager&, LCompilers::CompilerOptions&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)
    v.visit_asr((ASR::asr_t&)asr);
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5367, in LCompilers::ASR::BaseVisitor<LCompilers::ASRToLLVMVisitor>::visit_asr(LCompilers::ASR::asr_t const&)
    void visit_asr(const asr_t &b) { visit_asr_t(b, self()); }
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5343, in ??
    case asrType::unit: { v.visit_unit((const unit_t &)x); return; }
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5368, in LCompilers::ASR::BaseVisitor<LCompilers::ASRToLLVMVisitor>::visit_unit(LCompilers::ASR::unit_t const&)
    void visit_unit(const unit_t &b) { visit_unit_t(b, self()); }
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5064, in ??
    case unitType::TranslationUnit: { v.visit_TranslationUnit((const TranslationUnit_t &)x); return; }
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 936, in LCompilers::ASRToLLVMVisitor::visit_TranslationUnit(LCompilers::ASR::TranslationUnit_t const&)
    visit_symbol(*mod);
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5370, in LCompilers::ASR::BaseVisitor<LCompilers::ASRToLLVMVisitor>::visit_symbol(LCompilers::ASR::symbol_t const&)
    void visit_symbol(const symbol_t &b) { visit_symbol_t(b, self()); }
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5073, in ??
    case symbolType::Module: { v.visit_Module((const Module_t &)x); return; }
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 3141, in LCompilers::ASRToLLVMVisitor::visit_Module(LCompilers::ASR::Module_t const&)
    visit_procedures(x);
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 4186, in void LCompilers::ASRToLLVMVisitor::visit_procedures<LCompilers::ASR::Module_t>(LCompilers::ASR::Module_t const&)
    visit_Function(*s);
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 3940, in LCompilers::ASRToLLVMVisitor::visit_Function(LCompilers::ASR::Function_t const&)
    generate_function(x);
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 4138, in LCompilers::ASRToLLVMVisitor::generate_function(LCompilers::ASR::Function_t const&)
    this->visit_stmt(*x.m_body[i]);
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5387, in LCompilers::ASR::BaseVisitor<LCompilers::ASRToLLVMVisitor>::visit_stmt(LCompilers::ASR::stmt_t const&)
    void visit_stmt(const stmt_t &b) { visit_stmt_t(b, self()); }
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 5098, in ??
    case stmtType::Assignment: { v.visit_Assignment((const Assignment_t &)x); return; }
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/asr_to_llvm.cpp", line 4867, in LCompilers::ASRToLLVMVisitor::visit_Assignment(LCompilers::ASR::Assignment_t const&)
    llvm_utils->deepcopy(value_struct, target_struct,
  File "/home/tanay/lcompilers/lpython/src/libasr/codegen/llvm_utils.cpp", line 1969, in LCompilers::LLVMUtils::deepcopy(llvm::Value*, llvm::Value*, LCompilers::ASR::ttype_t*, llvm::Module*, std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, int, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, int, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, int> > > > > >&)
    if( !LLVM::is_llvm_struct(ASRUtils::symbol_type(item.second)) &&
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr_utils.h", line 312, in ??
    return ASRUtils::expr_type(
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr_utils.h", line 286, in ??
    return ASR::expr_type0(f);
  File "/home/tanay/lcompilers/lpython/src/libasr/../libasr/asr.h", line 52456, in ??
    switch (f->type) {
  Binary file "/lib/x86_64-linux-gnu/libc.so.6", in __GI___sigaction()
Segfault: Signal SIGSEGV (segmentation fault) received

[tanay-man]

@certik , @Thirumalai-Shaktivel according to cpython this shouldn't create a deepcopy but just a reference. Should this be modified to align with cpython behaviour?
Ex:

from lpython import i32

class coord:
    def __init__(self:"coord", x:i32):
        self.x: i32 = x 

p1: coord = coord(1)
p2: coord = p1
p2.x = 2
print(p1.x)
print(p2.x)

Lpython output :

(lp) tanay@tanay-man:~/lcompilers/lpython$ lpython  ../constructor.py 
1
2

Cpython output:

(lp) tanay@tanay-man:~/lcompilers/lpython$ python  ../constructor.py 
2
2

[certik]

This has been discussed in #1746 (comment). We either do not allow p2 = p1 at all, or we must ensure p1 is not used after the assignment.