Marcel Taeumel uploaded a new version of FFI-Kernel to project FFI:
http://source.squeak.org/FFI/FFI-Kernel-mt.79.mcz

==================== Summary ====================

Name: FFI-Kernel-mt.79
Author: mt
Time: 30 May 2020, 4:56:51.283231 pm
UUID: 2191ddfe-e9ae-844c-bf19-71cc0ab214dd
Ancestors: FFI-Kernel-mt.77

Fixes a bug with wrong byte alignment for double and longlong and ulonglong on 32-bit non-ARM Unix-based platforms.

Start documenting Squeak FFI's relationship to "int" and "long" with the flag #ffiLongVsInt. If you spot an implication somewhere, just put this flag in the code.

Because byte alignment is stored in atomic types, re-initialize those if the platform changed on image start up. This also affects structure types.

(Skip mt.78 because that number rests in our treated inbox for now.)

=============== Diff against FFI-Kernel-mt.77 ===============

Item was changed:
  ----- Method: ExternalStructure class>>install (in category 'system startup') -----
  install
+ 	"Resume the system on a new platform. Recompile all structures to account for different word size etc."
- 	"Resume the system on a new platform. Recompile all structures to accound for different word size etc."
  	
  	self recompileStructures.!

Item was changed:
  ----- Method: ExternalType class>>initializeAtomicTypes (in category 'class initialization') -----
  initializeAtomicTypes
  	"ExternalType initialize"
+ 	
  	| atomicType byteSize type typeName byteAlignment |
+ 	self flag: #ffiLongVsInt. "For a discussion about long vs. int see http://forum.world.st/Re-squeak-dev-64-bit-FFI-was-porting-Croquet-to-Squeak6-0-alpha-tp5113318.html."
+ 	
  	#(
  		"name		atomic id		byte size	byte alignment"
  		('void' 		0 				0			0)
  		('bool' 		1 				1			1)
  		('byte' 		2 				1			1)
  		('sbyte' 	3 				1			1)
  		('ushort' 	4 				2			2)
  		('short' 		5 				2			2)
+ "!!!!!!"	('ulong' 	6 				4 "!!!!!!"		4)
+ "!!!!!!"	('long' 		7 				4 "!!!!!!"		4)
+ 		('ulonglong' 8 				8			8) "v.i."
+ 		('longlong' 	9 				8			8) "v.i."
- 		('ulong' 	6 				4			4)
- 		('long' 		7 				4			4)
- 		('ulonglong' 8 				8			8)
- 		('longlong' 	9 				8			8)
  		('char' 		10 				1			1)
  		('schar' 	11 				1			1)
  		('float' 		12 				4			4)
+ 		('double' 	13 				8			8) "v.i."
+ "TODO: ('longdouble' 14			10			16? 4?)"
- 		('double' 	13 				8			8)
  	) do:[:typeSpec| | compiled |
  		typeName := typeSpec first.
  		atomicType := typeSpec second.
  		byteSize := typeSpec third.
  		byteAlignment := typeSpec fourth.
+ 		
+ 		"0) On 32-bits Windows and MacOS, double and long long have an alignment of 8. But on 32-bit Linux, their alignment is 4. But not on a 32-bit Raspberry Pi OS."
+ 		(FFIPlatformDescription current wordSize = 4
+ 			and: [FFIPlatformDescription current isUnix
+ 			and: [FFIPlatformDescription current isARM not]]) ifTrue: [
+ 				(#('double' 'longlong' 'ulonglong') includes: typeName) ifTrue: [
+ 					byteAlignment := 4]].
+ 		
+ 		"1) Regular type"
- 		"On 32 bits Windows and MacOS, double and long have an alignment of 8. But on Linux, their alignment is 4"
- 		(FFIPlatformDescription current wordSize = 4 and: [FFIPlatformDescription current isUnix]) ifTrue: [
- 			(#('double longlong ulonglong') includes: typeName) ifTrue: [
- 				byteAlignment := 4
- 			]
- 		].
  		compiled := WordArray with: ((byteSize bitOr: FFIFlagAtomic) bitOr:
  				(atomicType bitShift: FFIAtomicTypeShift)).
  		type := (AtomicTypes at: typeName).
+ 		type
+ 			compiledSpec: compiled;
- 		type compiledSpec: compiled;
  			byteAlignment: byteAlignment.
+ 		
+ 		"2) Pointer type"
  		compiled := WordArray with: ((self pointerSpec bitOr: FFIFlagAtomic) bitOr:
  				(atomicType bitShift: FFIAtomicTypeShift)).
  		type asPointerType
  			byteAlignment: self pointerAlignment;
  			compiledSpec: compiled.
  	].!

Item was added:
+ ----- Method: ExternalType class>>platformChangedFrom:to: (in category 'system startup') -----
+ platformChangedFrom: lastPlatform to: currentPlatform
+ 	"Byte size or byte alignment for atomic types might be different on the new platform."
+ 	
+ 	self initializeAtomicTypes.
+ 	self initializeStructureTypes.!

Item was changed:
  ----- Method: FFIPlatformDescription class>>startUp: (in category 'system startup') -----
  startUp: resuming
  	"Notify all FFI classes about platform changes."
  
  	resuming ifTrue: [
  		LastPlatform in: [:lastPlatform | self newCurrent in: [:currentPlatform |
  			lastPlatform = currentPlatform
  				ifTrue: [
  					self flag: #discuss. "mt: Maybe add #platformResuming?"
  					ExternalAddress allBeNull]
  				ifFalse: [
  					LastPlatform := currentPlatform. "Update now. See #current."
+ 					{ ExternalType. ExternalAddress. ExternalObject. FFIExternalSharedPool }
- 					self flag: #discuss. "mt: Maybe directly call ExternalStructure?"
- 					{ ExternalAddress. ExternalObject. FFIExternalSharedPool }
  						do: [:cls | cls
  							platformChangedFrom: lastPlatform
  							to: currentPlatform] ]]] ].!