Add FPC_SYSTEM_EXIT_NO_RETURN macro for embedded target

* compilation fixes for many platforms after 0041167

* AVR: due to recent fixes, EXCLUDE_COMPLEX_PROCS is not needed anymore

+ Xtensa: RTL skeleton

+ Xtensa: completed rtl skeleton

esp8266: Make startup code compile.

+ Xtensa: mathu.inc using only the softfloat unit provided mechanisms

+ Xtensa: add linklib statements, better _halt procedure

* FreeRTOS: do not try to build native utils

* build more units for FreeRTOS

+ forgotten files added

* patch by Michael Ring: adds license headers to th FreeRTOS files and some renames to make the interrupts cmsis compatible.

* Xtensa: fpc_setjmp dummy

+ implemented get_caller_addr and get_caller_frame for the Z80

+ added empty strings.inc and stringss.inc files

zxspectrum: pascal startup code. this allows the RTL to be built with any assembler

+ initialize StackBottom and StackLength in the startup of the ZX Spectrum system unit

zxspectrum: in the pascal startup code, match start symbol name with the asm startup code

* fixed compilation with sdld

+ Xtensa: Sptr

+ add support for port object on Z80 using the new IN/OUT intrinsics

* fixed stack initialization in the ZX Spectrum startup code

+ clear the .bss section on startup in the ZX Spectrum RTL

* patch by Christo Crause: embedded heap manager: free small blocks, resolves 0037204

* switch to interrupt mode 2 and install a custom maskable interrupt handler in
the ZX Spectrum startup code, because the ROM handler requires the IY register
to always have a specific value, but the FPC code generator uses the IY
register for various purposes, which causes random crashes and glitches when
the timer interrupt occurs.

Add softfpu feature for z80 cpu

+ patch by Christo Crause: ESP8266 controller unit for freertos, resolves 0037336

Add -SfPROCESSES for arm cpu, to be able to compile fcl-base package as for xtensa

- remove local Random() implementations that weren't exported anyway (LongInt <> Integer inside the System unit)

* Xtensa: patch by Christo Crause: add support for windowed ABI stack dump, resolves 0037583

* StackTop must be OS specific (and not CPU specific)

* reduce number of default libs

+ initial implementation of setjmp/longjmp

* TThread.Terminate does not have any platform specific behavior (it should only set FTerminated to true and call TerminatedSet), thus move it to the platform independant part
Notes:
- Netware had a ThreadSwitch in there, but that is not really required
- some platform were missing the setting of FTerminated to True, thus they'll now do that as well

* Xtensa FreeRTOS: unified haltproc

* compilation fixed

Move z80 specific -Sf options from rtl.cfg to system.cfg, as -Sf options are only accepted when compiliing system unit

* Xtensa-FreeRTOS: use setjmp/longjmp provided by the Xtensa libraries, we
have to link against them anyways

+ dummy implementation for FreeRTOS threading support

* enable initialization of exceptions and threading on FreeRTOS

Fix problems in xtensa fpc_setjmp/fpc_longjmp for linux

z80-zxspectrum: delete and remove the prt0.asm file. it's not used any more, as it doesn't contain the interrupt code required for stable operation of the target, and this removes sdasz80 dependency from the RTL build process, if another assembler is used by the compiler

* rtl: implement TRandomGenerator for thread-safe random

* revert 0047598: implement TRandomGenerator

* patch by Christo Crause to take care of the fact that the esp8266 read function is non-blocking, resolves 0038243

* Set softfloat_rounding_mode indise SetRoundMode function for all CPUs.
* SetRoundMode returns previous rounding mode value for all CPUs.

* (modified) patch by Michael Ring to enable the FPU on Cortex-M4F if available

* patch by Michael Ring to fix errors introduced by 0048722

* CortexM4: Add some missing system registers

+ skeleton of an embedded thread manager

* set no result in NoBeginThread, it never returns

* HaltProc does not return

* patch by Christo Crause: Xtensa [patch] Use syscall 0 to spill registers on ESP32, resolves 0039221

Add license headers

Add wasm32 CPU handling in embedded target

Add libraries required to link simple example with esp8266-rtos-sdk v3.3

* embedded: cleanup of the dummy DOS unit. remove the stubs for platform-specific helpers, cleanup tabs/spaces, cleanup the copyright-message mess

* cleanup

* enable random on avr, it does not increase program size if not used

* anonymous method overloads for synchronize/queue.

* fix missing ifdef for the non win32/64/unix targets.
* also do watcom.

Split startup code into different .init sections according to avr-libs convention.

* Char -> AnsiChar

* Char -> AnsiChar

* Char -> AnsiChar

* string -> shortstring

* string -> shortstring

* move $H here

* Synchronize API for AnsiString/Unicode string, keep string where possible.

* unit name fixed

* library list for esp32c3 for IDF 5.0

* typo fixed

Change m68k-embedded target to handle standard RTL units as most other CPUs do (fixes compilation failure in utils/h2pas package)

Use same features for riscv32 as for arm and xtensa CPUs

Fix spaces/tab issue

Remove fpcmake.loc added by accident

Fix z80-embedded target

Call rtl_do_close handler in sysfile.do_close, as reported by Kostas Michalopoulos

* Add delphi-compatible observers to classes

* Do not use namespace prefix for lnfodwarf

Disable THREADING on embedded aarch64

With THREADING enabled, you get a NoThreadError at startup
when using the classes unit.

Add efuse library to default list of static link libraries.

Fix missing configuration for namespaces to make rp2040.pp build on main compiler

embedded, arm, stm32: Fix CAN register definition

- bxCAN controller only has 2 RX mailboxes.
The registers behind were misplaced.
Refer to RM0008 section 24.9.3 and 24.9.4

Simplify required link libraries and move libc, libm and libgcc to end.

* Added nothreads unit for fake thread support. Currently only WASI

Add esp32c3 units to namespaced.

+ added unit unix98pty. Only enabled for linux, for now, but can be enabled in the future on other unix-likes.

- remove unused variables

- remove unused variables

* switch Z80 RTL to provide atomic intrinsic helpers instead of Interlocked* functions

* switch Xtensa RTL to provide atomic intrinsic helpers instead of Interlocked* functions

* trailing spaces removed

Add intrinsics dependency in classes unit for several OSes

Set FPC_USE_INTRINSICS when appropriate for most platforms

Set FPC_USE_INTRINSICS after _USES clause for i386 and x86_64

Also disable FPC_USE_INTRINSICS on i386 and x86_64 if LLVM or for version < 3.3.1

+ intrinsics unit for x86-64

+ intrinsics unit for i386

+ intrinsics unit for i386