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    <head>
      <base href="https://bugs.llvm.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - GlobalOpt emits debug fragments with wrong offsets for padded fields"
   href="https://bugs.llvm.org/show_bug.cgi?id=36016">36016</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>GlobalOpt emits debug fragments with wrong offsets for padded fields
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>new-bugs
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>trunk
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>new bugs
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>david.stenberg@ericsson.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=19712" name="attach_19712" title="IR reproducer.">attachment 19712</a> <a href="attachment.cgi?id=19712&action=edit" title="IR reproducer.">[details]</a></span>
IR reproducer.

LLVM commit used: r322927.

When running:

  opt -globalopt -S foo.ll -o -

on the attached reproducer, a fragment expression with an offset of 32 bits is
created for the second field in the struct:

  !14 = !DIGlobalVariableExpression(var: !7, expr:
!DIExpression(DW_OP_LLVM_fragment, 32, 64))

However, as the field is padded up to 64 bits:

  !12 = !DIDerivedType(tag: DW_TAG_member, name: "bar_p", scope: !8, file: !3,
line: 3, baseType: !13, size: 64, offset: 64)

that fragment offset is incorrect.

The reproducer was created by compiling the following program, foo.c:

  struct {
    int foo;
    int *bar_p;
  } static var;

  int *ptr;

  int main() {
    if (var.foo == 0)
      var.bar_p = ptr;
    return 0;
  }

using:

  clang -march=x86-64 -O0 -g2 -S -emit-llvm foo.c -o foo.ll</pre>
        </div>
      </p>


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