Memory allocations produced via alloca have function scope

[tautschnig]

We must not mark the allocation as dead when leaving the block, but instead need to defer that until the end of the function.

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[codecov]

Codecov Report

Base: 78.35% // Head: 78.35% // Increases project coverage by +0.00% 🎉

Coverage data is based on head (d397f58) compared to base (c7550b6).
Patch coverage: 98.07% of modified lines in pull request are covered.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #7375   +/-   ##
========================================
  Coverage    78.35%   78.35%           
========================================
  Files         1645     1645           
  Lines       190182   190208   +26     
========================================
+ Hits        149015   149040   +25     
- Misses       41167    41168    +1     

Impacted Files	Coverage Δ
src/goto-programs/goto_convert_class.h	88.15% <ø> (ø)
src/goto-programs/builtin_functions.cpp	60.02% <97.91%> (+1.01%)	⬆️
src/goto-programs/goto_convert_functions.cpp	100.00% <100.00%> (ø)

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[peterschrammel]

Do we need a second test that checks deallocation when returning from the function?

[tautschnig]

Good point, I'll expand the test to that effect (even though I do think we cover this case in the test alloca-02).