guess how much memory will be needed and adjust chunk size
reboot hpohl's #2470
fix Issue 13071 - [ICE] dmd 2.066.0-b1 assertion in nogc.c:73
Merge pull request #3730 from 9rnsr/fix13071

[REG2.066a] Issue 13071 - [ICE] dmd 2.066.0-b1 assertion in nogc.c:73
fix Issue 13081 - ICE with alias this and opSlice
Merge pull request #3732 from 9rnsr/fix13081

[REG2.066a] Issue 13081 - ICE with alias this and opSlice
fix Issue 12989 - Wrong x86_64 code for delegate return when compiled as lib
[trivial] Fix warning in cast.c
fix Issue 13088 - Compiler segfaults with trivial case code
fix Issue 13087 - Error: no property 'xyz' for type 'Vec!4'
Merge pull request #3735 from WalterBright/fix12989

fix Issue 12989 - Wrong x86_64 code for delegate return when compiled as...
Merge pull request #3613 from WalterBright/hpohl-opt

Increase allocation chunk size + minor refactoring
Merge pull request #3736 from 9rnsr/fix13087

[REG2.066a] Issue 13087 - Error: no property 'xyz' for type 'Vec!4'
fix Issue 11066 - Spurious warning 'statement is not reachable' with -profile
[Refactoring] in FuncDeclaration::semantic3
fix Issue 13024 - [ICE](expression.c line 1172) with implicit supertype conversion of different enums in array literal
fix Issue 13082 - Spurious error message with failed call to class ctor
Merge pull request #3733 from 9rnsr/fix13024

[REG2.066a] Issue 13024 - [ICE](expression.c line 1172) with implicit supertype conversion of different enums in array literal
fix Issue 13074 - Old opCmp requirement for AA keys should be detected
Fixed build with XCode.