SDCC-STD-UX

SDCC-STD-UX is a German federally funded 6 month project to improve standard compliance and usability in SDCC.
It is mostly about improving standard compliance (ISO C standards, DWARF. Focus: ISO C23) when targeting µC architectures.

Possible tasks:

Priority from 1 (most important) to 5 (least important). Criteria for priorities: Has the feature been requested by users often? Is the feature necessary for older standards beside C23? Is it particularly relevant for µC? Is it mandatory in the standard(s)?

Note: The "New parser, suitable for C23" Task is special, since many other C23 tasks depend on it.

Priority	Category	Task	Tickets	Developer	Status
1	C90-C23	Support struct / union return	[feature-requests:#167] [bugs:#2846]	@spth	DONE
1	C90-C23	Support struct / union parameter	[feature-requests:#23]	@spth	DONE
2	C99-C23	Compound literals	[feature-requests:#332]	@roybaer	POSTPONED (WIP)
2	Debug	Debug info fixes	[bugs:#3200] [bugs:#2970] [bugs:#2870] [bugs:#2741] [bugs:#2906] [support-requests:#151]		POSTPONED
2	C11-C23	_Generic fixes	[bugs:#3145] [bugs:#3255]	@spth	DONE
2	C90-C23	Type system fixes	[bugs:#3254] [bugs:#2629] [bugs:#2766]	@spth	DONE
2	C90-C23	Function declaration fixes	[bugs:#3091] [bugs:#2664] [feature-requests:#776]	@spth	DONE
3	C90-C23	brace omission in array initalization	[feature-requests:#562]	@roybaer	POSTPONED (WIP)
3	C99, C23	variably-modified types	[feature-requests:#786]	@spth	DONE
3	Debug	ELF/DWARF for mcs51			POSTPONED
3	C23	Modernize preprocessor (possibly by rebasing our fork on the one from GCC 11)	[bugs:#3159] [feature-requests:#466]	@felixs	DONE
3	C23, Usability	assert	[feature-requests:#780]	@spth	DONE
3	Usability	Fix type range warnings	[bugs:#3094] [bugs:#2877]		POSTPONED
3	C23	typeof	[feature-requests:#738] [feature-requests:#739]	@spth	DONE
3	C23	New parser, suitable for C23	[feature-requests:#809]	@spth	MOSTLY DONE
3	C23	attributes	[feature-requests:#654]		MOSTLY DONE
3	C23	Bit-precise integer types	[feature-requests:#681]	@spth	DONE
3	C99-C23, Usability	Segfault in loop	[bugs:#2981]	?	DONE
3	Usability, C90-C17	Include GCC 11 tests in regression tests	[feature-requests:#698]	@felixs	DONE
3	Usability, C90-C99	Include QuickC tests in regression tests	[feature-requests:#697]	@felixs	DONE
3	Usability, C90-C99	Include tinycc tests in regression tests	[feature-requests:#696]	@felixs	DONE
3	Usability	GCC-style command line options	[feature-requests:#733]	@roybaer	DONE
3	Usability	F2X headers	[feature-requests:#33]		rejected
3	Usability	STM8-Wizard für Code::Blocks? Maybe have a look at https://github.com/retiredfeline/codeblocks-wizard-stm8/tree/master/stm8 and maybe merge to upstream Code::Blocks?			POSTPONED
3	Usability	IDE integration? Code::Blocks, PlatformIO (might work already https://github.com/platformio/platform-ststm8/issues/31, but affected by SDCC bugs: https://github.com/microsoft/vscode-cpptools/issues/7146), Eclipse?			POSTPONED
3	C23	Enhanced enumerations	[feature-requests:#847]		POSTPONED
3	C23	auto	[feature-requests:#849]	@spth	DONE
3	C23	bit utilities	[feature-requests:#854]	@spth	DONE
4	C23	Checked integer arithmetic	[feature-requests:#749]	@spth	MOSTLY DONE
4	C23	Identifier syntax	[feature-requests:#775]	@roybaer	POSTPONED (concept)
4	C23	Invalid Unicode warning	[feature-requests:#781]	@spth	DONE
4	Usability	Get rid of invalid warnings	[bugs:#3108]		POSTPONED
4	Usability	Segfault on float initialization	[bugs:#3031]	@spth	DONE
4	C95-C23	Segfault on wide string literals	[bugs:#3030]		POSTPONED
4	C90-C17	K & R declarations	[bugs:#3021] [feature-requests:#450]	@roybaer	POSTPONED (concept)
4	C23	{} initialization	[feature-requests:#782]	@spth	DONE
4	C23	keywords	[feature-requests:#783]	@spth	DONE
4	C23	unreachable	[feature-requests:#778]	@spth	DONE
4	C23	UTF-8 literal type char8_t	[feature-requests:#779]	@spth	DONE
4	C99-C23	New modular C23-compliant implementation of the printf family	[feature-requests:#768]	@roybaer	POSTPONED (WIP)
4	Usability	Allow multiple C source files on command line	[feature-requests:#657]	@roybaer	POSTPONED (WIP)
4		SDCC developer meeting in summer, to discuss progress and coordinate		many	DONE
4		Present results at FrOSCon 2022		@spth	DONE
4	Usability	Fails to build on current Debian GNU/Linux	[bugs:#3140]		POSTPONED
4	C90-C23	Full/improved floating point support	[bugs:#3396] [feature-requests:#304] [feature-requests:#324] [feature-requests:#351] [feature-requests:#599] [feature-requests:#753]	@roybaer	POSTPONED (preparation)
4	C23	C2X variadic parameters	[feature-requests:#845]		POSTPONED
4	C23	memalignment	[feature-requests:#846]	@spth	DONE
4	C90-C23	enumeration types and constants	[bugs:#3462]	@spth	DONE
4	C23	qualifier-preserving stdlib functions	[feature-requests:#848]		POSTPONED
4	C23	constexpr	[feature-requests:#850]		POSTPONED
4	C23	nullptr	[feature-requests:#853]	@spth	DONE
4	C23	tag compatibility	[feature-requests:#852]	@spth	DONE
4	C23	label at end of compound statement	[feature-requests:#802]	@spth	DONE
5	Debug	ELF/DWARF for sm83			POSTPONED
5	C23	call_once	[feature-requests:#777]	@spth	DONE
5	Usability	GCC-compatible attribute syntax	[feature-requests:#682]	@roybaer	PARTIAL (WIP)
5	Usability	configure should check for makeinfo	[bugs:#3192] [bugs:#3288]		POSTPONED
5	Usability	Documentation tarball contains intermediate files	[bugs:#3345]	@spth	work in progress
5	C23	[[unsequenced]] [[reproducible]]	[feature-requests:#851]	@spth	DONE

Further relevant feature request: [feature-requests:#666].

Fortnightly progress reports:

2022-03-07:

Done: Kick-off-workshop, paperwork, create this page, setup internal communication channel (Matrix).
Doing: Unit tests. Check meeting minutes of recent SC22 WG14 meetings for relevant new C23 features already approved. Open tickets for individual features. List, priorize and categorize relevant tasks here (see above).
Motivation: Quality assurance, getting started.

2022-03-21:

Done: Onboarding. Derived relevant C23 tasks (see above) from SC22 WG14 meeting minutes, categorized and priorized them. C23 assert. C23 char8_t.
Doing: Unit tests (port tests from GCC, QuickC, Tiny C to SDCC). C23 bit-precise integer types. C90-C23 struct / union return. C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O.
Motivation: Quality assurance. Standard compliance.

2022-04-05:

Done: C90-C23 struct / union return. C90-C23 struct / union parameters. C23 bit-precise integer types.
Doing: Refactor test infrastructure. Port tests from GCC, QuickC, Tiny C to SDCC. C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O.
Motivation: Quality assurance. Standard compliance.

2022-04-18:

Done: Various small fixes.
Doing: Refactor test infrastructure. Port tests from GCC, QuickC, Tiny C to SDCC. C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Fixes for the type system and C11 _Generic selections.
Motivation: Quality assurance. Standard compliance, usability.

2022-05-03

Done: Fixes for the type system (in particular wrt. intrinsic named address spaces) and C11 _Generic selections.
Doing: Refactor test infrastructure. Port tests from GCC, QuickC, Tiny C to SDCC. C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Merge current upstream GNU binutils into SDCC fork.
Motivation: Quality assurance. Standard compliance, usability. Code quality.

2022-05-16

Done: Refactor test infrastructure. Port tests from GCC, QuickC, Tiny C to SDCC. C23 warning on invalid Unicode codepoints.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Merge current upstream GNU binutils into SDCC fork.
Motivation: Quality assurance. Standard compliance, usability. Code quality.

2022-05-30

Done: Merge current upstream GNU binutils into SDCC fork. Classify failures in new tests adopted from GCC, TinyC, QuickC. Check impact of ISO SC22WG14 May meeting C23 decisions on SDCC.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Modernize preprocessor.
Motivation: Quality assurance. Standard compliance, usability. Code quality.

2022-06-13

Done: SDCC developer meeting 1. Bugfixes.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Modernize preprocessor. New parser.
Motivation: Standard compliance, in particular foundations for further progress towards C23 compliance. Share preprocessor code between GCC and SDCC.
Challenges: Single out preprocessor out of large GCC codebase. Relicense an existing upstream parser under a free license so we can use bits of it in our new one.

2022-06-27

Done: Negotiated relicensing of C23 reference parser. Bugfixes.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Modernize preprocessor. New parser. GCC-style command line options.
Motivation: Standard compliance, in particular foundations for further progress towards C23 compliance. Share preprocessor code between GCC and SDCC.
Challenges: Single out preprocessor out of large GCC codebase. Implement C23 capabilities in parser without breaking backwards compability with SDCC language extensions too much.

2022-07-11

Done: GCC-style command line options. Improve floating-point support. Present some related work, in including bits of a possible successor project at FSiC 2022.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Modernize preprocessor. New parser. Apply for (non-PT) funding for a possible successor project.
Motivation: Standard compliance, in particular foundations for further progress towards C23 compliance. Share preprocessor code between GCC and SDCC. Learned about the relevance of SDCC for freedom in mobile devices (Replicant developers want to use SDCC to build free firmware for microcontrollers embedded in smartphone pripherals).
Challenges: Clean up preprocessor build. Implement C23 capabilities in parser without breaking backwards compability with SDCC language extensions too much.

2022-07-25

Done: Bugfixes. Completed list of tasks based on final set of features of the C23 standard (which was decided at the ISO SC22WG14 meeting 2022-07-18 to 2022-07-22). Preparations for the preprocessor modernization.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Modernize preprocessor. New parser. Apply for (non-PT) funding for a possible successor project.
Motivation: Standard compliance; we now know the final set of features for C23, which (apart from too many restriction on the use of -bit-precise integer types) seems reasonable.
Challenges: Clean up preprocessor build. Implement C23 capabilities in parser without breaking backwards compatibility with SDCC language extensions too much. Wonder, how much of all those new C23 features we will be able to implement, and how to prioritize.

2022-08-08

Done: Various Bugfixes. Applied for (non-PT) funding for a possible successor project. Basic VLA type support. C23 {} empty initializers. Function declaration fixes. C23 auto. C23 typeof and typeof_unqual. C2x unreachable. C23 memalignment. C23 nullptr.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O. Modernize preprocessor. New parser. Implement bit and byte utilities standard library functions. C23 attributes.
Motivation: Standard compliance; trying to get done more standard compliance tasks, even if that means postponing some of the debug support and usability-related tasks.
Challenges: Enhanced enums and some corner cases of attributes non-trivial to support in parser. Remaining time likely unsufficient to complete all remaining tasks.

2022-08-22

Done: Preprocessor modernization. New parser. Implement bit and byte utilities standard library functions. C23 attributes. C23 tag compatibility. C23 call_once. Bugfixes. FrOSCon talk.
Doing: C11-C23 compound literals. GCC attribute syntax compatibility. C23 modular formatted I/O.
Motivation: C23 standard compliance; trying to get done C standard compliance tasks, even if that means postponing some of the debug support and usability-related tasks.
Challenges: Time running out.

2022-09-05

Done: Demo Day.
Doing: Writing final report. Bugfixes.
Challenges: Project ended.