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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 - ld.lld overaligns TLS segment"
   href="https://bugs.llvm.org/show_bug.cgi?id=41527">41527</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>ld.lld overaligns TLS segment
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>lld
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </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>ELF
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>eleviant@accesssoftek.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org, peter.smith@linaro.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Commit r350681 introduced overalignment of TLS segment for Android
compatibility which however breaks normal AArch64/Linux images when
initial-exec TLS model is used. One possible way to implicitly enable such TLS
model is to use -fsanitize=hwaddress.

Steps to reproduce:
1. Create two C source files: main.c and so.c

/* File: so.c */
extern __thread long tlsvar;

void foo() {
  tlsvar = 10;
}

/* File: main.c */
#include <assert.h>
__thread long tlsvar;
void foo();
int main() {
  foo();
  assert(tlsvar == 10);
  return 0;
}

2. Build executable and shared object to run on Linux/AArch64:
clang -target aarch64-pc-linux -fpic -shared -ftls-model=initial-exec -o
libtlsvar.so so.c -fuse-ld=lld

clang -target aarch64-pc-linux -fpie main.c libtlsvar.so -o main -fuse-ld=bfd

3. Run main - assert will fire.</pre>
        </div>
      </p>


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