<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/143246>143246</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            MLIR Regression: 54 tests started to fail recently
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            mlir
      </td>
    </tr>

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

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

<pre>
    I've been seeing these errors for almost 2 weeks now.
They have been reproduced on aarch64-linux and x86_64-linux.

I have been able to bisect these failures to #141248.

This is the output of one of the tests:
```
******************** TEST 'MLIR :: Transforms/constant-fold-debuginfo.mlir' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
/builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/llvm/redhat-linux-build/bin/mlir-opt /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir -split-input-file -test-constant-fold -mlir-print-debuginfo | /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/llvm/redhat-linux-build/bin/FileCheck /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir
# executed command: /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/llvm/redhat-linux-build/bin/mlir-opt /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir -split-input-file -test-constant-fold -mlir-print-debuginfo
# executed command: /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/llvm/redhat-linux-build/bin/FileCheck /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir
# .---command stderr------------
# | /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir:5:17: error: CHECK-NEXT: expected string not found in input
# |  // CHECK-NEXT: [[C:%.+]] = arith.constant 6 : i32 loc(#[[UnknownLoc:.*]])
# | ^
# | <stdin>:2:27: note: scanning from here
# |  func.func @fold_and_merge() -> (i32, i32) {
# |                           ^
# | <stdin>:3:4: note: possible intended match here
# |  %c6_i32 = arith.constant 6 : i32
# |    ^
# | /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir:20:12: error: CHECK: expected string not found in input
# |  // CHECK: arith.constant 1.{{0*}}e+00 : f32 loc(#[[UnknownLoc:.*]])
# | ^
# | <stdin>:10:42: note: scanning from here
# |  func.func @materialize_different_dialect() -> (f32, f32) {
# | ^
# | <stdin>:11:9: note: possible intended match here
# | %cst = arith.constant 1.000000e+00 : f32
# |         ^
# | /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir:33:17: error: CHECK-NEXT: expected string not found in input
# |  // CHECK-NEXT: arith.constant 6 : i32 loc(#[[UnknownLoc:.*]])
# |                 ^
# | <stdin>:18:33: note: scanning from here
# |  func.func @materialize_in_front(%arg0: memref<8xi32>) {
# | ^
# | <stdin>:19:12: note: possible intended match here
# |  %c6_i32 = arith.constant 6 : i32
# |            ^
# | 
# | Input file: <stdin>
# | Check file: /builddir/build/BUILD/llvm-21.0.0_pre20250526.gc76e2800e3d78f-build/llvm-project-c76e2800e3d78fa6e8618431a6893f66f2fd3496/mlir/test/Transforms/constant-fold-debuginfo.mlir
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |             1: module { 
# |             2:  func.func @fold_and_merge() -> (i32, i32) { 
# | next:5'0 X~~~~~~~~~~~~~~~~~~ error: no match found
# |             3:  %c6_i32 = arith.constant 6 : i32 
# | next:5'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | next:5'1          ? possible intended match
# |             4:  return %c6_i32, %c6_i32 : i32, i32 
# | next:5'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |             5:  } 
# | next:5'0 ~~~
# |             6: } 
# | next:5'0       ~~
# |             7:  
# | next:5'0       ~
# |             8: // ----- 
# | next:5'0 ~~~~~~~~~
# |             9: module { 
# | next:5'0       ~~~~~~~~~
# | 10:  func.func @materialize_different_dialect() -> (f32, f32) { 
# | next:5'0       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | check:20'0 X~~~~~~~~~~~~~~~~~~ error: no match found
# |            11:  %cst = arith.constant 1.000000e+00 : f32 
# | check:20'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | check:20'1 ?                                  possible intended match
# | 12:  return %cst, %cst : f32, f32 
# | check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            13:  } 
# | check:20'0 ~~~
# |            14: } 
# | check:20'0     ~~
# |            15:  
# | check:20'0     ~
# |            16: // ----- 
# | check:20'0 ~~~~~~~~~
# |            17: module { 
# | check:20'0     ~~~~~~~~~
# | 18:  func.func @materialize_in_front(%arg0: memref<8xi32>) { 
# | check:20'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | next:33'0 X~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
# | 19:  %c6_i32 = arith.constant 6 : i32 
# | next:33'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | next:33'1                 ? possible intended match
# |            20:  affine.for %arg1 = 0 to 8 { 
# | next:33'0      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            21: memref.store %c6_i32, %arg0[%arg1] : memref<8xi32> 
# | next:33'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            22:  } 
# | next:33'0      ~~~
# |            23:  return 
# | next:33'0 ~~~~~~~~
# |            24:  } 
# | next:33'0      ~~~
# | .
# |             .
# |             .
# | >>>>>>
# `-----------------------------
# error: command failed with exit status: 1
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzsWVtv2zoS_jX0y0CCROrmBz84vmCD7Z4Fuilw3gJaGtncyqRBUk26D_vbF6TsWokt5-LuQU5xCLVxFM74m-H3DYcSN0asJeKEpDcknY94azdKT2zbCLUdrVT1fXJLaP4NYYUowSAKuQa7QYOAWittoFYaeLNVxgKFB8SvBqR6CEk0vdvgd9jwg7HGnVZVW2IFSgLnutxkSdAI2T4ClxU8Ftn94YYzJ9H0tmfOVw2CVbASBku7x1Bz0bQajfsDoSxOYpoUe-O7jTAgjJsJqrW71oKqQUl0P9xNi8YawtxckkX7K5oS-v4L7hb_ugNC8398uv0Mzjebwp3m0tRKbw2hy1JJY7m0Qa2aKqhw1a6FrFW4bYQmNIfl9PbTYg7XgCDRdPEoLMxUhe774y4fM7Xdujz_s8sFoYWxlWotoeMuCUHgo2fw-ctvzo5baITEzp4uV61oqsqh7D4Surz5cvtpTuiyab5tAxqHURjd7zTSiKZRSrNwXeYZ0iKKkFV5UQcHOz9_p9W_sbTB0zk8wyKLi4TFPCvGrM6ymtYVS8bZ3o7QpcZqw23HlB8-V0ISunRpDNTOhfcRAHerunRMI3T5aiJAYHaNsIGQu9YGtWgQAucjeGIEgY92p4W0RwdA8tkHif7l5VqKBmcbLL9-EMTvXK-9bvARy9ZiBWUnNSeijxHXX8J5WTi_wCL-WnIKgyDYLwIYW6HWQW_sJ32cavfeYNk0JWwa545ovqdyH2Z_W8z-Hvy2-P3O337cYek4aax2DZhUFmrVygqEBM_1XjZcOghdPnPhG7ybmdvpaRoS6to9ks6BsDlwLewmPICEzDUuIBiFRpWEFoSyzvqL_CrVg_ykSsKmoes0vA_XQPQWI130f2MzYyshCVsQNqXunw9UKut7E1NyKV1ItVZb2KDGfiR1K8vQ_QckiVzu7rms7reo1-hxjSEgbOFaGcEooTPwP8ZA8pu-m8FxCSsjbJr0oe6UMcI1oUJalBVWsOW23JyAJjQts3uXvku5fYrvGZA_OZ9p5AhNTwl9HZd9T_o0nXHoljq_iRwZ8znJ50joTRT5LNf_BwbHLrSEvpPCW25RC96I_-B9JeoaNUp7XwneYGmfMbruGF2fY_RFhDFh0_E7iOt4a-w50sZh5MfT3J5R2K9FY8b-gLr8U2vvW-pbXBxCvJbJQt7XWsmOwCnXa6cR2OJWY03YrHh05Y4t3kjj8Y8a8kcU4IGMHT_eutUE11H63bSH9Tina71-zPlT0_9sEoKq3e665pqw-QabnZNAw4XsHrPUqmnUg2OQnwNuengpnw_88ADmSILn13l6x55jqmobdKyCgWmeQNf0EX3HEh-tb9doHsHv_z0ZxzIh1Z6bvhoMYPPaeyVbB2Gcong-zlvGPc6z5ZC2BpD7vgg02lbLYwAucf1oOpl12bwC_5MI-iPt8pfPLzkfsM28Qi-YdmPQPu---7LxgG2xrw5uM_BHmZeTM-BpPCyCs8GcevP9zM_sUl6L4Q1rXrqy2rWVP0V4vkOCN_c7MAzpTZENhhZ7Jb44XpZqt2329emKf6_D6_q3bt0uhPXqMPrJZedUeep4wDo5o8uzyR6wT5_r8pzxgG12SZdDqRnwlQ8r8xJ3-otYXFbm27quK8l7KmrGhsT4akn6Fu-KDXAP4U2C65vGJ9J6805Iu_LJ61pIDGuloVuL2McSgVVQDFTFPfqX0z_wzfFxuUNjlcaTjdhzIr3ZI-oe9pxhyDWZfTVaemGvfpaJAQ_sSU17CfKAk-RdMMKB7fc19_1p5um1_2MWBZfG4XH0QUaHJ6E1Fw1W8CDsBvBRWDCW29b8eNF3eJM5qiasGrMxH-EkzpMxHVMaZ6PNJEnjok7r1TgromK8WhUpYxHnbFyWY7oqs5GY-NNIFuVxxKI4C6uiquooqaJVnOdZXpMkwi0XTegOJaHS65EwpsVJnDCaZKOGr7Ax_pUypd35g5J0PtITf4hZtWtDkqgRxpqjBytsgxP_2vQzrjUaI5R0QaVJ96LWxandWdsqnwPQWKK0zfdRq5vJxtqdP0r48r0WdtOuwlJtj4_N-wcoQpcesTsF7UF_m9D_BQAA__-qvfMS">