Fix Issue 5908 - Optimizer generates wrong value with divide-by-zero.

Reinstate optimizer error for integer division by zero
[Refactoring] simplify the code to inherit @safe attribute
[Refactoring] simplify the code in checkPurity
fix 9148 - Issue 9148 - 'pure' is broken
Remove hack for issue 10981
fix Issue 9620 - Error messages of failed pure enforcement
fix Issue 12912 - Lambda function is incorrectly inferred as impure if it uses member field or function
fix Issue 12908 - [AA] `foreach` by keys and values over associative array in pure function allow impure function calls
fix Issue 13120 - Body of `foreach` over string with transcoding ignores function attributes
fix Issue 3449 - const and invariant struct members do not behave according to spec
AA tests harmonization with new AA implementation
do not generate __fieldPostBlit if this(this) annotated with @disable
Comment out non-compilable AA literal
@disable __fieldPostBlit if any of postblits[] are disabled.
Fix-up type inference for function literals whose returns have been modified.
Merge pull request #4073 from IgorStepanov/disiabled-field-postblit

do not generate __fieldPostBlit if this(this) annotated with @disable
Issue 13460 - dmd can no longer be built with DEBUG=1 on Linux/x86_64
Merge pull request #4079 from IgorStepanov/checkedinn-not-compiled-in-with-debug

Issue 13460 - dmd can no longer be built with DEBUG=1 on Linux/x86_64
use an array instead of a list for global symbol list

- significantly speeds up library creation

- slist_reset is still extremely expensive
faster StringTable

- use a hash table with open addressing and linear probing
  for better cache locality