<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/121718>121718</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Flang] Compilation abnormally terminates when derived type and interface statement with the same name is defined and used in two modules
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            flang
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          ohno-fj
      </td>
    </tr>
</table>

<pre>
    ```
Version of flang : 20.0.0(c5492e3c65e40cdcab9771b692f9ad437c65aa04)/AArch64
```

The attached program has two modules with the same name (`iand`) below.  
- The first module (`m1`) has `type-param-name-list` of `derived type`.  
- The second module (`m3`) has `type-param-name-list` in `derived type` and `generic-spec` in `interface` statement.

In this case, a compilation terminates abnormally.  
The program uses only the definition of module (`m1`).  
I suspect that the existence of unused module (`m3`) definitions should not affect the behavior.  

The following actions for the program result in successful compilation:
- Module (`m3`) is deleted. or,
- Rename `type-param-name-list` in `derived type` and `generic-spec` in `interface` statement in module (`m3`) to something other than iand.

The following are the test program, Flang, Gfortran and ifx compilation/execution result.

snggz898_21.f90:
```fortran
module m1
  type iand
 integer:: x1=1
     integer:: x2=2
  end type iand
contains
  subroutine foo
    write(6,*) "iand(2,3) = ", iand(2,3)
  end subroutine foo
end module m1
module m3
  interface iand
     integer function zzz(x1,x2) result(r)
       character:: x1
       integer:: x2
     end function zzz
  end interface iand
  type iand
     integer:: x1=1
     character:: x2='2'
  end type iand
end module m3

program main
  use m1
  use m3
 call foo
  print *,'pass'
end program main

integer function zzz(x1,x2) result(r)
  character:: x1
  integer:: x2
  read(x1,*) k
  r=k+x2
end function zzz
```

```
$ flang snggz898_21.f90

fatal internal error: CHECK(localSymbol->has<UseDetails>()) failed at /work/groups/ssoft/compiler/llvm/src/llvm-main/flang/lib/Semantics/resolve-names.cpp(3481)
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.      Program arguments: /work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang -fc1 -triple aarch64-unknown-linux-gnu -emit-obj -mrelocation-model pic -pic-level 2 -pic-is-pie -target-cpu generic -target-feature +outline-atomics -target-feature +v8a -target-feature +fp-armv8 -target-feature +neon -resource-dir /work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/lib/clang/20 -mframe-pointer=non-leaf -o /tmp/snggz898_21-f89bf6.o -x f95-cpp-input snggz898_21.f90
 #0 0x000040000de135d0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/work/groups/ssoft/compiler/llvm/aarch64/main-latest/lib/libLLVM.so.20.0git+0x5a035d0)
 #1 0x000040000de11658 llvm::sys::RunSignalHandlers() (/work/groups/ssoft/compiler/llvm/aarch64/main-latest/lib/libLLVM.so.20.0git+0x5a01658)
 #2 0x000040000de117b0 SignalHandler(int) Signals.cpp:0:0
 #3 0x00004000034707a0 (linux-vdso.so.1+0x7a0)
 #4 0x0000400012c76274 raise (/lib64/libc.so.6+0x36274)
 #5 0x0000400012c60a2c abort (/lib64/libc.so.6+0x20a2c)
 #6 0x0000000006ae94d4 (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x6ae94d4)
 #7 0x0000000005ea5610 Fortran::semantics::ModuleVisitor::DoAddUse(Fortran::parser::CharBlock, Fortran::parser::CharBlock, Fortran::semantics::Symbol&, Fortran::semantics::Symbol const&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5ea5610)
 #8 0x0000000005ea61d4 Fortran::semantics::ModuleVisitor::Post(Fortran::parser::UseStmt const&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5ea61d4)
 #9 0x0000000005eba074 Fortran::semantics::ResolveNamesVisitor::Pre(Fortran::parser::SpecificationPart const&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5eba074)
#10 0x0000000005eba5c4 std::enable_if<TupleTrait<Fortran::parser::SpecificationPart>, void>::type Fortran::parser::detail::ParseTreeVisitorLookupScope::Walk<Fortran::parser::SpecificationPart, Fortran::semantics::ResolveNamesVisitor>(Fortran::parser::SpecificationPart const&, Fortran::semantics::ResolveNamesVisitor&) resolve-names.cpp:0:0
#11 0x0000000005ec02a8 Fortran::semantics::ResolveNamesVisitor::ResolveSpecificationParts(Fortran::semantics::ProgramTree&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5ec02a8)
#12 0x0000000005ec06d4 Fortran::semantics::ResolveNamesVisitor::Pre(Fortran::parser::ProgramUnit const&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5ec06d4)
#13 0x0000000005ec0fac Fortran::semantics::ResolveNames(Fortran::semantics::SemanticsContext&, Fortran::parser::Program const&, Fortran::semantics::Scope&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5ec0fac)
#14 0x0000000005f8532c Fortran::semantics::Semantics::Perform() (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x5f8532c)
#15 0x00000000057dbc78 Fortran::frontend::FrontendAction::runSemanticChecks() (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57dbc78)
#16 0x00000000058c7064 Fortran::frontend::CodeGenAction::beginSourceFileAction() (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x58c7064)
#17 0x00000000057dd30c Fortran::frontend::FrontendAction::beginSourceFile(Fortran::frontend::CompilerInstance&, Fortran::frontend::FrontendInputFile const&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57dd30c)
#18 0x00000000057ce3b8 Fortran::frontend::CompilerInstance::executeAction(Fortran::frontend::FrontendAction&) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57ce3b8)
#19 0x00000000057e1adc Fortran::frontend::executeCompilerInvocation(Fortran::frontend::CompilerInstance*) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57e1adc)
#20 0x00000000057c6b90 fc1_main(llvm::ArrayRef<char const*>, char const*) (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57c6b90)
#21 0x00000000057c65e8 main (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57c65e8)
#22 0x0000400012c64384 __libc_start_main (/lib64/libc.so.6+0x24384)
#23 0x00000000057c4ab4 _start (/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang+0x57c4ab4)
flang-20: error: unable to execute command: Aborted (core dumped)
flang-20: error: flang frontend command failed due to signal (use -v to see invocation)
flang version 20.0.0git (https://github.com/llvm/llvm-project.git c5492e3c65e40cdcab9771b692f9ad437c65aa04)
Target: aarch64-unknown-linux-gnu
Thread model: posix
InstalledDir: /work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin
Build config: +assertions
flang-20: note: diagnostic msg:
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
flang-20: note: diagnostic msg: /tmp/snggz898_21-4a6a94
flang-20: note: diagnostic msg: /tmp/snggz898_21-4a6a94.sh
flang-20: note: diagnostic msg:

********************
$
```

```
$ cat /tmp/snggz898_21-4a6a94
#line "./snggz898_21.f90" 1
      module m1
 type iand
      integer:: x1=1
      integer:: x2=2
      end type iand
 contains
      subroutine foo
      write(6,*) "iand(2,3) = ", iand(2,3)
      end subroutine foo
      end module m1
      module m3
 interface iand
      integer function zzz(x1,x2) result(r)
 character:: x1
       integer:: x2
      end function zzz
      end interface iand
      type iand
      integer:: x1=1
      character:: x2='2'
      end type iand
      end module m3

      program main
 use m1
      use m3
      call foo
      print *,'pass'
      end program main

      integer function zzz(x1,x2) result(r)
      character:: x1
 integer:: x2
      read(x1,*) k
      r=k+x2
      end function zzz
$
```

```
$ cat /tmp/snggz898_21-4a6a94.sh
# Crash reproducer for clang version 20.0.0git (https://github.com/llvm/llvm-project.git c5492e3c65e40cdcab9771b692f9ad437c65aa04)
# Driver args: "snggz898_21.f90"
# Original command: "/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang" "-fc1" "-triple" "aarch64-unknown-linux-gnu" "-emit-obj" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-target-cpu" "generic" "-target-feature" "+outline-atomics" "-target-feature" "+v8a" "-target-feature" "+fp-armv8" "-target-feature" "+neon" "-resource-dir" "/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/lib/clang/20" "-mframe-pointer=non-leaf" "-o" "/tmp/snggz898_21-f89bf6.o" "-x" "f95-cpp-input" "snggz898_21.f90"
 "/work/groups/ssoft/compiler/llvm/aarch64/main-20241223-c5492e3c65e4/bin/flang" "-fc1" "-triple" "aarch64-unknown-linux-gnu" "-emit-obj" "-mrelocation-model" "pic" "-pic-level" "2" "-pic-is-pie" "-target-cpu" "generic" "-target-feature" "+outline-atomics" "-target-feature" "+v8a" "-target-feature" "+fp-armv8" "-target-feature" "+neon" "-mframe-pointer=non-leaf" "-x" "f95-cpp-input" "snggz898_21-4a6a94"
$
```

```
$ gfortran snggz898_21.f90; ./a.out
 iand(2,3) =            2           3
 pass
$
```

```
$ ifx snggz898_21.f90; ./a.out
 iand(2,3) = 2           3
 pass
$
```


</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzsWk1v2zqz_jXMhpAhUbZsL7JwnPi0uH3fFk16zjKgqJHNE4kUSMpJ--sv-CHLVux8tU1xgWu0gUWOhvM8MyTHHFKt-VoAnKPJBZpcntHWbKQ6lxsho_Lfs1wW389RFod_8eJvUJpLgWWJy4qKNUbpApN4FI9iRGZsMp4TSFk2gXHMCkbz-XSa5NmclHNajNMpyyaUxmNE5oisFgvFNtkYxYv9EVC8uNkApsZQtoECN0quFa3xhmps7iWuZdFWoPE9NxtsNoA1rQEL-weRGcpiTkVhVZE5zqGS9yOMUbyIsNVacqVNUBHE6yQI2wFQFpvvDUQNVbSOrNKo4tqgLLaIURYXoPgWCmylUBbv69bApCgGytOXKefiiHJMRWGb1yBAcRbpBlgvzIUBVVLmJLWhBmoQZuQZ_Ciw2XCNGdWAyBJTzGTd8Ioa6zwDquaCGtCY5kKqmlbVdw_FAukYbzVoLEX13dFcQMkFN8H5Ryn0Kj5i3VpTDTYbaty78MC1AcHAvtqKVsMpnvpRNNYb2VYFFtJgWpZeIeAcNnTLpfKDBZNLWVXynos1psy_XErlxDswCnRbGcudbhkDrcu22icFpQvnyf8cNYtrXEAFBooRlgqRpZP9Cj7s3sGvtvM4Y0ZiLWswG4temg1Y3FRgOw1GRxlS4JgxoE1Hj42RlZ3P9stfpVRGUeHs5OXDAU1kBQ_AWhcHntMwiBbr9Y_ZfHZLklE5jz2fu4kdVKJ4EVDUCYoX2FHiTLVPFvoalH01XeCHBKWXXgrjYR9B6SVxfSCKAy1MCkO50K5Tt7mSreHCEiCDrnvFDSAyy6wfycKSiAhxr5MZQWSZuqb00jZbQgZdu2EfaYd-_jt83ffUvbLz7A7wHjBctsKFLv7x4wcis4cEkeUDsZZ4mhGZqW5w92Ebqigz-3zt-h6xFXqsgQcDdVCO2HbgmiNKD9zzyBjrIESmBJHpUTftU5X6COqmak25cO-0ehcn7qujkdGq2jmzUVwY7Jy4RGTaUK39gFb9QB-KF2_h-gTNRxlWQItOX4isO9-B0ss7RC6c3BEnDDbAg0cyDlvtcIY50ZIaWnn3CVphUEpao_Dyw9XyfxCZVZLR6vp7ncsqQunVhmqULr9puARDeaVRemXXE7sfz3FJeQUFppbR1b1Ud4is1kq2jUZkpbUsDSIrvxiAQmRVVdva9igWHiJHNVmVfilZVTxHZHUNNRWGM6tFgZbVFtwqqUesaRCZpeNZ4tn-8ulqcX1l51XNDaY4b9dYQSOVscvcxphGW8LJyhrGzabNR0zWvSXOhkbJf4FZU7nWLdhR_UomWNUWfu1jiuoNzim7M4oysEvYtaHsDhdt3fily-7t9vMlRBFV69auxNaC1_FDqc9zyMrSE5GYjBNC0mg_W0JklffU4ahkCY6M4k0FOLwfteJOyHsRVVy0D9FatDiCmptI5v_iqFZgXW1jKqplARVuOMNRw1lUwRYqTPwD11HDAUeGqjWYiDUtDvvQrq0EalplN5oL2ZqKC4iokTVn-pjIdkaPNZdNRFW9nR3rEyAFjmwotIpBVHD1Wwj10cdCLJIYR3Wp7O7cSDdfUHoppIgqoCWOpDXB1I0duJ9nUTmb52U2kjh6wOV8ErGmibhoWnNkNmJE0hjHD3Ecx2P7p4AknRQxdma7hUJ_1_7LF7twuZC7sQFoJ-pOSNH7W6mNArsvZ24DEsbvUrOf4amyGZ_ZEVPx_NOnv_8z0nJkE_g1N4hcxA8TGlujw_KHSJoMICXZZHYM0tdWXPO1oNUHKooKlPYLy7tZbe3qrSZDq6d5jA_sQ2QWePXNfjlKF7H777Wk-1rS8TSe0tgC8lNwW2hpDUmcCVO6R9p478WEsGlGpmOsKNcQ-Kh4noUgZVZH5nSkVq7XMjnUksWUMExzux4-pYVYuV5LFrS4T0ZhPi7GP-uVFyxizpQwXG_MdN-YCdBJlsR4FbJDH1C77cI9-oT8b665kWG7vZSLovhmf9nMDt5sqNLdlrzcUHVRSXbnUtvXSw2s8DtomI7PC2ImhQ3a7BdMgJdSHcjsqZ4NqM6SYvxaqr9IC-M0zd80XJva_CG8FlGPd36IN6fx9Gm8X30y8l-bixyiVk_G1nUDjJfc77ZfqPpD8B1AD98u0_EQ_oSNsTaFtxkEzSu45SVKlzdtU8GNotygdPlylC5XXOKt5IX96oRcSn9SReGSzMCpbb9R0MXXJynv2uaayQa8wD-0unudPc9MxaPuvXqrY18_lg-Hxxlvv8VYtyWHbmMxobO3RW3oeARCDyEPFIYM1_rmvUPYoe1DmAy5yJ5Zsd46gwPkb4L_obnroPXA0yHwkrIXA3_GvbufX0spDDwcjeYj3Lw49P0Ufnf-Ssp6_sYH_JWzSUqe5u96MAVAlVLVvyZjfTEKb2ePYnKAYlrkbDpYCkplfSjCmr4KTwvWnWCmC9WKDttyA-zuF2XhL8bkre4xHSSfkxmbxtn4KUxLWcBfIPYh5bDm4tr9VlzxCkLX-8LyhvewpgNXFWnMXuuqAa7hNB7y4qF8FNpQweDYxDw-5Ef7c9UO8EdWOk9NT9xhUjplkOZPxvgj3D6bcWfQfSi8nPl3Ru_w9egPU9QpJLR4MmwCzp6EbTjjeW2wLN4VtcO1Q03igc-zfB7jkiW3_rhw7-hjoRT9_hVskso2VHURuwip52Hbu_rR2twjSoaIJjBz58zvadEE-sgiZHBUME5nY3x7W_Gc3WpDlbndM-_EsYF9p9eYDjCOaT7GXtc7orSjeptcc0Rs7twfc7fuZw02Eoepgpmsa-omAl7kUhkorLVMKnCHu1A8oc0fvnZzqVPVnYsXrRtIu9Miq7TVgKOtawPAfG9y7kbA21Aw9zXyNXfcve4ke2Tfek1pPV7cuDNXC-nk4bGrCyqgrgwD9kcabqTmD656rA2tKiguufqdp93x4qLlleVZlHztR7qgWoNyNdyBl4Q0dvXHBadrIbXhDNd6HeqM5Cf-uTpKKD0sbm4Wyw_45sMVXn3-9OnzPx__-xdeffx0dY1vPrvmi29_4a9XXz5_vfFDf1HQKMlAayiwP9FGZKbt6mRjh2otGac2DFUrsGaKN2YnoAC7U3tXdfH6XgT5-GH1mGZ0Pv4VOkZ68xr2f94B5Mg1kGEVjPnC1BO4EUkrLgAjQkaHMu6InhDc10gP6tCPap1PFjtPF6O7GuuBvoOKtP0crUr_orp0Z8GJMYYV6kMu0q4K_7hM_ZY69Vsq1MdL1F3HCdte6b5ni9VH3fiIv1C29h3D4vVe7dp--vq1t2C_iO1fP1HI7od9XM5-s2OeuD9w0i8na9uuc7--fdKPv2KW-5UJkRQvXQ3Xrb5FyywBUmH2Bzdda9Sl4ltQmKp1qBOTx4tQEP2s-JrbTGIvY3ET-zfnVcSOEpUs6b76MnN4Op0vBOmu5Nw9Pyo8h46Gs05kV4QODWS_wxekd7bsytKhJRSnB_2hmBxaHxeqnxPfzuhzIl0B-zk5ATbh8zL7Je2dxO8vbO9ccaq83QnI3qjTpe5O-CF8OSh7h7ajQf3_0ft_O3qfDZ8XRkSXj4WV7gVr_rq7cfjoEuEFtokcHcnWuN3pSDK09yF7391m6_bRFxrBy4c3jf-qQc-K87SYp3N6BufJNM0Sks3jydnmPCFAaT6mMS1JMgWWlPk8pXPGWJZm02J8xs9JTCZxEmdxQmZkMsrmWToZJwXNcpjGU0DjGGrKq5GdXSOp1mfu_tN5QpJpMjuraA6Vdve8CekmE5pcnqlzt-_l7VqjcVxxbXSvwnBTucvh_nbo5BIv9y4S97eH9-8U329A4P07r-H6VZe69Zdaj9zhdjdtSy7sLyJRYHdVmIv9m99nrarO334XLNCxPSf_GwAA__-FDSUO">