fix Issue 3753 - ICE(eh.c): Related to exception handling and alloca.
fix Issue 11233 - DMD HEAD very slow with large static array struct field
fix Issue 11230 - Inexact mangling for template function literal.
fix Issue 11242 - Fails to infer template argument with inout
fix Issue 11228 - alias this confuses static array copy
fix Issue 11256 - Error mixing struct with disabled default construction and templated with lambda struct
Fix ICE case 1 in issue 11256
Fix ICE case 2 in issue 11256
Merge pull request #2663 from 9rnsr/fix11242

[REG2.064a] Issue 11242 - Fails to infer template argument with inout
Merge pull request #2664 from 9rnsr/fix11228

[REG2.063] Issue 11228 - alias this confuses static array copy
Merge pull request #2666 from 9rnsr/fix11256

[REG2.063] Issue 11256 - Error mixing struct with disabled default construction and templated with lambda struct
fix Issue 11257 - Allow whole implicit conversion if one or more overlapped field could.
fix Issue 9665 - Structure constant members can not be initialized if have opAssign

- Change the first field assignment inside constructor to true initialization.
- Disable multiple initialization of non-mutable field, if it is once initialized.
fix Issue 11246 - [REG 2.063] Struct initialized in constructor is destroyed first
fix Issue 11261 - Can't infer types without explicit slice in foreach
Merge pull request #2668 from 9rnsr/fix11261

[REG2.064a] Issue 11261 - Can't infer types without explicit slice in foreach
fix Issue 11271 - auto ref opAssign + destructor + struct literal fails
fix Issue 11265 - Segfault while calling instance method of class defined inside struct

The regression was introduced by the commit:
https://github.com/D-Programming-Language/dmd/commit/671b7c20b96b580ee1dc2b3f5e3ee66c63d079b6#diff-43282ebf5a2de5fdbcb3b5083ddf949dR147

vtbl[] calculation is essentially unrelated to the class instance size.
So, just only once initializing of vtbl[] and running semantic on member
functions is sufficient.
fix Issue 11215 - `inout` lose enclosing `shared` on resolution
Merge pull request #2670 from 9rnsr/fix11265

[REG2.064a] Issue 11265 - Segfault while calling instance method of class defined inside struct