[clang] [LifetimeSafety] Handle escape through assignment to global storage (PR #181646)

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github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 52552 tests passed
* 959 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### Clang
<details>
<summary>Clang.Sema/warn-lifetime-analysis-nocfg.cpp</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
c:\_work\llvm-project\llvm-project\build\bin\clang.exe -cc1 -internal-isystem C:\_work\llvm-project\llvm-project\build\lib\clang\23\include -nostdsysteminc -fsyntax-only -Wdangling -Wdangling-field -Wreturn-stack-address -verify C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\clang.exe' -cc1 -internal-isystem 'C:\_work\llvm-project\llvm-project\build\lib\clang\23\include' -nostdsysteminc -fsyntax-only -Wdangling -Wdangling-field -Wreturn-stack-address -verify 'C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp'
# note: command had no output on stdout or stderr
# RUN: at line 2
c:\_work\llvm-project\llvm-project\build\bin\clang.exe -cc1 -internal-isystem C:\_work\llvm-project\llvm-project\build\lib\clang\23\include -nostdsysteminc -fsyntax-only -Wlifetime-safety -Wno-dangling -verify=cfg,cfg-field C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\clang.exe' -cc1 -internal-isystem 'C:\_work\llvm-project\llvm-project\build\lib\clang\23\include' -nostdsysteminc -fsyntax-only -Wlifetime-safety -Wno-dangling -verify=cfg,cfg-field 'C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp'
# .---command stderr------------
# | error: diagnostics with 'warning' severity expected but not seen: 
# |   File C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp Line 163 'cfg-warning': object whose reference is captured does not live long enough
# |   File C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp Line 173 'cfg-warning': object whose reference is captured does not live long enough
# | error: diagnostics with 'note' severity expected but not seen: 
# |   File C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp Line 163 'cfg-note': destroyed here
# |   File C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp Line 165 'cfg-note': later used here
# |   File C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp Line 173 'cfg-note': destroyed here
# |   File C:\_work\llvm-project\llvm-project\clang\test\Sema\warn-lifetime-analysis-nocfg.cpp Line 175 'cfg-note': later used here
# | 6 errors generated.
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/181646