Normalize backend's elf structures with system headers.
Forward to system headers when available.
implement UDA for module declaration
[Refactoring] checkNonAssignmentArrayOp
fix issue 13497 remained case

`AssignExp::semantic` should handle cases in both valid and invalid array operations.
fix Issue 12381 - [ICE] An internal error in e2ir.c while casting array ops
warn on .sort and .reverse usage
make typedef an error
fix Issue 13550 - Inner functions take outer function attributes erroneously
add new cdpopcnt to stub platform
Merge pull request #4031 from 9rnsr/fix13550

[REG2.067a] Issue 13550 - Inner functions take outer function attributes erroneously
Merge pull request #4032 from braddr/fix-stub

add new cdpopcnt to stub platform
Merge pull request #4028 from WalterBright/warn-sort-reverse

warn on .sort and .reverse usage
Merge pull request #4011 from 9rnsr/fix_arrayop

[REG2.065] Issue 13497 & 12381 - fix remaind e2ir ICE around array ops
Merge pull request #4029 from WalterBright/typedef-error

make typedef an error
fix Issue 13356 - [ICE] (dmd 2.066: statement.c:754) with recursive Algebraic
[Refactoring] Remove goto jumps
fix Issue 11888 - Incorrect behaviour taking slice from return value
fix Issue 13563 - ICE with opIndexAssign op-overloading and ModuleScopeOperator
fix Issue 13564 - nested struct destructor trying to access members of a global class fail to compile
Fix x64 compilation with MSVC