<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/89514>89514</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [BUG] Clang crashes when compiling IR
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          maxomatic458
      </td>
    </tr>
</table>

<pre>
    ```llvm
define i64 @main()  {
entry:
; let num = 17
%_3 = alloca i64
store i64 17, i64* %_3
%_2 = load i64, i64* %_3
%_num_1 = alloca i64
store i64 %_2, i64* %_num_1
%_5 = load i64, i64* %_num_1
%_7 = alloca i64
store i64 0, i64* %_7
%_6 = load i64, i64* %_7
%_8 = icmp eq i64 %_5, %_6
br i1 %_8, label %if_9, label %else_9 
if_9:

; return 0
%_11 = alloca i64
store i64 0, i64* %_11
%_10 = load i64, i64* %_11
ret i64 %_10
else_9:

%_13 = load i64, i64* %_num_1
%_15 = alloca i64
store i64 1, i64* %_15
%_14 = load i64, i64* %_15
%_16 = icmp eq i64 %_13, %_14
br i1 %_16, label %else_9, label %end_if9 
else_9:

; return 1
%_18 = alloca i64
store i64 1, i64* %_18
%_17 = load i64, i64* %_18
ret i64 %_17
br label %end_if9
end_if9:

; return 0
%_20 = alloca i64
store i64 0, i64* %_20
%_19 = load i64, i64* %_20
ret i64 %_19
}
```

trying to compile this with ``clang out.ll``
will throw this error:
```
warning: overriding the module target triple with x86_64-pc-windows-msvc19.36.32535 [-Woverride-module]
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: "C:\\Program Files\\LLVM\\bin\\clang.exe" -cc1 -triple x86_64-pc-windows-msvc19.36.32535 -emit-obj -mrelax-all -mincremental-linker-compatible -dumpdir a- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name out.ll -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -fdebug-compilation-dir=C:\\Users\\User\\Desktop\\compiler\\compiler2 -fcoverage-compilation-dir=C:\\Users\\User\\Desktop\\compiler\\compiler2 -resource-dir "C:\\Program Files\\LLVM\\lib\\clang\\18" -ferror-limit 19 -fmessage-length=209 -fno-use-cxa-atexit -fms-extensions -fms-compatibility -fms-compatibility-version=19.36.32535 -fskip-odr-check-in-gmf -fdelayed-template-parsing -fcolor-diagnostics -faddrsig -o C:\\Users\\User\\AppData\\Local\\Temp\\out-5d0151.o -x ir out.ll
1.      Code generation
2.      Running pass 'Function Pass Manager' on module 'out.ll'.
3.      Running pass 'X86 DAG->DAG Instruction Selection' on function '@main'
Exception Code: 0xC0000005
 #0 0x00007ff731d5434f (C:\Program Files\LLVM\bin\clang.exe+0x277434f)
 #1 0x00007ff731767344 (C:\Program Files\LLVM\bin\clang.exe+0x2187344)
 #2 0x00007ff7316cc2ce (C:\Program Files\LLVM\bin\clang.exe+0x20ec2ce)
 #3 0x00007ff7316b0673 (C:\Program Files\LLVM\bin\clang.exe+0x20d0673)
 #4 0x00007ff7316af20b (C:\Program Files\LLVM\bin\clang.exe+0x20cf20b)
 #5 0x00007ff7317f3616 (C:\Program Files\LLVM\bin\clang.exe+0x2213616)
 #6 0x00007ff72f997699 (C:\Program Files\LLVM\bin\clang.exe+0x3b7699)
 #7 0x00007ff731682efe (C:\Program Files\LLVM\bin\clang.exe+0x20a2efe)
 #8 0x00007ff7316a3d43 (C:\Program Files\LLVM\bin\clang.exe+0x20c3d43)
 #9 0x00007ff72f922091 (C:\Program Files\LLVM\bin\clang.exe+0x342091)
#10 0x00007ff72f921b5d (C:\Program Files\LLVM\bin\clang.exe+0x341b5d)
#11 0x00007ff72f91b9e9 (C:\Program Files\LLVM\bin\clang.exe+0x33b9e9)
#12 0x00007ff72fc92876 (C:\Program Files\LLVM\bin\clang.exe+0x6b2876)
#13 0x00007ff72fb8d8e1 (C:\Program Files\LLVM\bin\clang.exe+0x5ad8e1)
#14 0x00007ff72fb8d382 (C:\Program Files\LLVM\bin\clang.exe+0x5ad382)
#15 0x00007ff72fb8a0b4 (C:\Program Files\LLVM\bin\clang.exe+0x5aa0b4)
#16 0x00007ff72fb87c30 (C:\Program Files\LLVM\bin\clang.exe+0x5a7c30)
#17 0x00007ff72fb865fe (C:\Program Files\LLVM\bin\clang.exe+0x5a65fe)
#18 0x00007ff72f9c607c (C:\Program Files\LLVM\bin\clang.exe+0x3e607c)
#19 0x00007ff72f9c1cc3 (C:\Program Files\LLVM\bin\clang.exe+0x3e1cc3)
#20 0x00007ff731ae4050 (C:\Program Files\LLVM\bin\clang.exe+0x2504050)
#21 0x00007ffc7c207344 (C:\Windows\System32\KERNEL32.DLL+0x17344)
#22 0x00007ffc7cee26b1 (C:\Windows\SYSTEM32\ntdll.dll+0x526b1)
clang: error: clang frontend command failed due to signal (use -v to see invocation)
clang version 18.1.4
Target: x86_64-pc-windows-msvc
Thread model: posix
InstalledDir: C:\Program Files\LLVM\bin
clang: note: diagnostic msg: Error generating preprocessed source(s) - no preprocessable inputs.
```

it seems to crash because the label ``else_9`` is defined 2 times
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJy0WF1v5CjW_jXODaJk4--LXCSpZDR6M69G3T07u1cRhuMqJhi8gJPKv18d7CTlUibZLmmjlpqC8zznE8yBe692BuAyKa-TcnvBp7C37nLgBzvwoERRNhedlS-XSZXO_7R-GpJ0m6RXEnplgKiqIEmRDlyZhDUJawlJ6utZBExwL0l-Nf9K8muiIRAzDSTJtySrl3lWPuRxhmttBUfKecUH62YNWZ2wm7jArkgEvGNZxGrL5Szwd3JmGh6yL_REvhOKiHunKT9TdyJbf6EuPYEfRaT6TM2RXBPllBhGAv9-86FEQKSZJTtHVBYnGlzRvAONP1X_0K4mQHt4aMmMiqtv6XtLooMwOUPSdyOyr-J66mh2FKQs_czVV0kH4c27bFE9G3tqIQrkP5GkrPyq-E5NKo_AxafGH0tWH2Yqy19TlRWnucqqD3KznjLyQfWv-fo4Hu8ZO3a6-VmnmyNw_anTzQcZq998O7X99aiYf_w31cbSn6w2dlyq7We2v0qubF9MTOrtMng9DI9NDe5FmR0Jlgg7jEoDCXvlybMKezJLC83NjtgpbLQ-xj8rrUnYO_s8Q8A5694DsVb2zJ1RZpfkV8Q-gXNKRq17IIOVE2rlbgeBBKdGDbP6Q1M9VAUdBX1WRtpnTwf_JLJ2k1ebnJV5SZLymv658AGdmZJycff3-9ur77fET92gAuGkm3bEwWhdQG_3IYwerWV3CbvbqbCfuo2wQ8Lu4rdi_o-Ozv4FIiTsTnk_gU_YHeFGEmWEniRED4Tjfk86Lh6D4wIwNaOD0VkB3oMk3k5unkYk994KxQNI4iZDvHBqDJvZ5O-Bi0cip2F8i2O6IfHvd2d3jg-Eu900gAloO0kYu0HJ8iYpb14l7pQGP0_d3__jt3nUKTMPYjY3cICEMUKFyAhdYv51uCkMKlDb_UXo4EDzA-VaEzooIxygUVxTrcwjOIrFxIPqNBCK_kjlCKeESuV5p4H2DoBQoYE7yn2gHfTWAcUggpHvcjEJT-BUr8DFacGdpE9cT0ANH8ATit9w2is9TyyVOptoBQ_KGiwN0GRUgtBRCarhCTRhhA694wPQ0SoTwCX51lgDhPYDD3sKzhlLaN-PVFiDuQ1JvrWG0N5Y6uxksIgpyhI6CGt8cJMI1lGuFfdoWj8ZDCYN6IxP8i0jdK50KsYJQ06rgtAwGYgTOzDg0MpeQjft6LwnZx-kQgPf8_2HB-ffh_NoC_4x2HHJ9byj3foXI7QXuGn4Dv5XChzMRY-cP1GlWnVHVToPsyZWah-PF6oVbuasxRyB9-iCBrMLe4xt2s6pmTxQceCUBziogKKewiGA8coaP_9-LVClVXj5YAqLDsWTfLvaAr1_VCO10lGxB_FIlaG7oY8J0_wFJA0wjJoHoCN3Hg85jLa2jkrFd8b6oASawKV0Xu0IteSLiF-N45YHvsTKCq7n4Q8YljTYKdBSplmZbSyhB6Lc63Edj5BsOUJurIS5wmK-50W2LH6bDB7QZOTek4TVd5MRKEV-x4nfuOE7cAmriTWvR3bC6kUNq5cDLP8btn82Fdle_UKT_HZ79Qv5ddkqyP8dNMTRQt6_Kk5Y_XZBXz7DtwcBY1xEX_AETA83afxbbiwkYXlK0gNO1X1f55ksi7zoScKaJc6nFbiU33xCHh2P1-mB1TWCE9a-s2cr9rqq86I4kz1rELxiZyv2Sggm4Ez2FBC8Ys_X7F1a1fm57BLBK_Zizc57lnbnsgsEr9jLddz7vMKb6VnsLEPwir06Ymd929ZV257HnneIXZHX68A0DPqzk8oRvGJvTsKey-LspAoEr9jbdWAYS9vszMAUiH0jx62UnpBnXSnPJUfsijxbk2ddC-emNEfsipytyEXLmvrMaqw6xK7I8xV518gGzox5yRG7Ii9OyfOGnU2eN2xFXp6Q87Q783AsOWJX5NUJeS3y9FxyxK7I6xPyqjx3j5YcsSvyZl2KokprcWYpAmJX5Cc7VGRCnLn_c0DsMTlbf0s5FGl5ZsxZmSJ4xX60RUUtWHryLf1z7kOS8ub7iw8w5Cwpb_7v9tv_397nbLO9v4_E2eojirRsRQvAqi77mPZf33_c_hZpTZBabyReZjCHCHnjnG-j-dVbi0vmnrh31gRsV4QdBuzteq40SCInwBbTq53hGhVPHgh9inMARJmnpS9ZayDLlZNkzSbbLK8DP2K3gDo_7s8Wqb0DLklsc1B2tF4d5iW8a3GtQW5VNP3rzK19NjbEm9b79ZUMPq7cYjTeLpR42_uo6218wlpCibFH69gOEWXGKfjNJ48TKmDABh-fJ-YuGwTHaGLfvbzIRNTyhBTHRHkyv_JKwkhQA_gLeZnLNm_5BVxmdZZXWIzFxf5SNLJtS8mKNIc870pWd5w3Xcsk5FXP0gt1yVJWpAVLGUvTtNgUUvJcyKbv-7zMeJYUKQxc6Q22qhvrdhfxpeCyacusuIg2-vhOzdgcU8aScnvhLmNr2007nxSpVj74d4aggo6P29d__JKUW3ITyyNGADx53oNZXmsw6r9-u5icvjz_QSNa-p8AAAD__zI5vm0">