Shortest infinite loop producing no output

Question

Your task is to create the shortest infinite loop!

The point of this challenge is to create an infinite loop producing no output, unlike its possible duplicate. The reason to this is because the code might be shorter if no output is given.

Rules

• Each submission must be a full program.
• You must create the shortest infinite loop.
• Even if your program runs out of memory eventually, it is still accepted as long as it is running the whole time from the start to when it runs out of memory. Also when it runs out of memory, it should still not print anything to STDERR.
• The program must take no input (however, reading from a file is allowed), and should not print anything to STDOUT. Output to a file is also forbidden.
• The program must not write anything to STDERR.
• Feel free to use a language (or language version) even if it's newer than this challenge. -Note that there must be an interpreter so the submission can be tested. It is allowed (and even encouraged) to write this interpreter yourself for a previously unimplemented language. :D
• Submissions are scored in bytes, in an appropriate (pre-existing) encoding, usually (but not necessarily) UTF-8. Some languages, like Folders, are a bit tricky to score - if in doubt, please ask on Meta.
• This is not about finding the language with the shortest infinite loop program. This is about finding the shortest infinite loop program in every language. Therefore, I will not accept an answer.
• If your language of choice is a trivial variant of another (potentially more popular) language which already has an answer (think BASIC or SQL dialects, Unix shells or trivial Brainf**k-derivatives like Alphuck), consider adding a note to the existing answer that the same or a very similar solution is also the shortest in the other language.
  
• There should be a website such as Wikipedia, Esolangs, or GitHub for the language. For example, if the language is CJam, then one could link to the site in the header like #[CJam](http://sourceforge.net/p/cjam/wiki/Home/), X bytes.
• Standard loopholes are not allowed.

(I have taken some of these rules from Martin Büttner's "Hello World" challenge)

Please feel free to post in the comments to tell me how this challenge could be improved.

Catalogue

This is a Stack Snippet which generates both an alphabetical catalogue of the used languages, and an overall leaderboard. To make sure your answer shows up, please start it with this Markdown header:

# Language name, X bytes

Obviously replacing Language name and X bytes with the proper items. If you want to link to the languages' website, use this template, as posted above:

#[Language name](http://link.to/the/language), X bytes

Now, finally, here's the snippet: (Try pressing "Full page" for a better view.)

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<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <link rel="stylesheet" type="text/css" href="//cdn.sstatic.net/codegolf/all.css?v=83c949450c8b"> <div id="language-list"> <h2>Shortest Solution by Language</h2> <table class="language-list"> <thead> <tr><td>Language</td><td>User</td><td>Score</td></tr> </thead> <tbody id="languages"> </tbody> </table> </div> <div id="answer-list"> <h2>Leaderboard</h2> <table class="answer-list"> <thead> <tr><td></td><td>Author</td><td>Language</td><td>Size</td></tr> </thead> <tbody id="answers"> </tbody> </table> </div> <table style="display: none"> <tbody id="answer-template"> <tr><td>{{PLACE}}</td><td>{{NAME}}</td><td>{{LANGUAGE}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr> </tbody> </table> <table style="display: none"> <tbody id="language-template"> <tr><td>{{LANGUAGE}}</td><td>{{NAME}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr> </tbody> </table>

Answer 1

Haskell, 8 bytes

main:x=x

One byte shorter than the classic main=main.

Answer 2

Vyxal, 1 byte

{

Try it Online!

-3 thanks to answering the right question

Explained

{      # Start an infinite while loop

Answer 3

C (GNU-EFI), 0 bytes

Yes, a C GNU-EFI program won't exit. You need to return for it to exit. Will not say anything, just hang.
And yes, it works with a standart GNU-EFI Makefile.
I used this one:

ARCH            = $(shell uname -m | sed s,i[3456789]86,ia32,)

OBJS            = main.o
TARGET          = main.efi

EFIINC          = /usr/include/efi
EFIINCS         = -I$(EFIINC) -I$(EFIINC)/$(ARCH) -I$(EFIINC)/protocol
LIB             = /usr/lib
EFILIB          = /usr/lib/
EFI_CRT_OBJS    = $(EFILIB)/crt0-efi-$(ARCH).o
EFI_LDS         = $(EFILIB)/elf_$(ARCH)_efi.lds

CFLAGS          = $(EFIINCS) -fno-stack-protector -fpic \
          -fshort-wchar -mno-red-zone -Wall
ifeq ($(ARCH),x86_64)
  CFLAGS += -DEFI_FUNCTION_WRAPPER
endif

LDFLAGS         = -nostdlib -znocombreloc -T $(EFI_LDS) -shared \
          -Bsymbolic -L $(EFILIB) -L $(LIB) $(EFI_CRT_OBJS)

all: $(TARGET)

main.so: $(OBJS)
    ld $(LDFLAGS) $(OBJS) -o $@ -lefi -lgnuefi

%.efi: %.so
    objcopy -j .text -j .sdata -j .data -j .dynamic \
        -j .dynsym  -j .rel -j .rela -j .reloc \
        --target=efi-app-$(ARCH) $^ $@

Hope this counts. And yes I tested this on a virtual machine.

Answer 4

Factor, 10 bytes

[ t ] loop

Try it online!

Factor is not necessarily verbose :P

Given that we need a quotation to repeat and a looping word, I believe this is the very shortest we can get in Factor.

Answer 5

Scratch, 23 bytes

A "forever" block still runs when it's empty.

when gf clicked
forever

Answer 6

Arduino, 27 bytes

void setup(){}void loop(){}

This is also the shortest Arduino code that will actually compile. I'm surprised no-one has done this yet.

Answer 7

Taxi, 22 20 bytes

[a]Switch to plan a.

Try it online!

Not very exciting. TIO will only run it for 60 seconds before timing out.

Answer 8

RISC-V machine code, 2 bytes

For CPUs implementing RV32I/E-C or RV64I-C:

01 a0 — c.j .

For RV32I/E-C CPUs only:

01 20 — c.jal .

RISC-V machine code (no extensions), 4 bytes

There are 4 sets of 32[1] instructions that work for this

6f 00 00 00 - j .
ef 00 00 00 - jal .
6f 01 00 00 - jal x2, .
...
ef 0f 00 00 - jal x31, .

The other 96 options are based on the conditional jump instructions beq, bge and bgeu with the same register as operands

[1]: 16 on RV32E

Answer 9

DC, 6 bytes

[dx]dx

It puts the constant string [dx] on the stack, duplicates it (d command), pops and interprets string (x command).

Answer 10

Spin, 13 Bytes

File x.spin:

pub x
 repeat

(without trailing newline)

Compile and download it to your P8x32a microcontroller or run it using spinsim.

Answer 11

AutoIt3, 12 bytes

While 1
WEnd

Simply loop indefinitely. Nothing much to say.

Answer 12

BBC Basic for Windows, 3 or 6

http://www.bbcbasic.co.uk/bbcwin/bbcwin.html

RUN

3 ASCII characters. Note in this version of BBC basic line numbers are not required.

If you don't consider termination and self-execution a loop, then the shortest program is

1GOTO1

6 ASCII characters.

One might expect these to be shorter in the tokenized version (1 byte per keyword), but it seems they are not, due to the way line numbers / internal ID's are stored.

Answer 13

GNU sed, 3 bytes

:;b

Using this meta answer as justification for the relaxation of the no-input rule.

: defines a (nameless) label, ; is a line/command separator, b jumps to the label.

Nameless labels seems to be a GNU extension.

Answer 14

Math++, 3 bytes

1>$

Basically a GOTO 1 statement- on line 1.

Answer 15

R, 9 8 bytes

repeat 1

Saved 1 byte thanks to MickyT!

Answer 16

Ada, 49 47 bytes

procedure L is begin loop null;end loop;end L;

I'm guessing there aren't many Ada entries on Code Golf!

Naturally it should look like

procedure L is 
begin 
   loop 
      null; 
   end loop; 
end L;

and do exactly what it says on the tin.

Answer 17

Self-modifying Brainfuck, 3 bytes

Same effect as in regular BF. Increment the cell and loop forever. -[] is the same.

+[]

Since the source code in placed on the tape, this is also acceptable, and only works in SMBF:

<[]

If the tape were actually infinite, [ or ] would work, since the interpreter would search for the matching bracket forever. Unfortunately (fortunately?), you just get an "index out of bounds" error.

Answer 18

Snowman 1.0.2, 6 chars

~:1;bD

~ sets all the variables to active, :...;bD is a "do" loop (i.e. continues looping while the block returns a truthy value), and 1 is 1.

Answer 19

AutoIt, 10 bytes

Do
Until 0

Lame.

Answer 20

ferNANDo, 7 bytes

1 1
1
1

Line 1 initializes 1 to 1, line 2 marks the beginning of the loop, and line 3 marks the end (a single variable statement loops back to the previous occurrence, if any, for as long as the variable is true).

Answer 21

Objective-C, 1716

-(id)a{for(;;);}

Answer 22

StackStream, 21 bytes

{ dup exec } dup exec

Kind-of explanation thingy:

{ dup exec } # Push this piece of code onto the data stack.
dup # Duplicate it (stack: { dup exec } { dup exec })
exec # Execute it (stack: { dup exec })

Answer 23

gs2, 2 bytes

CP437: ►3

Hex dump: 10 33

Tries to split whatever is on STDIN into chunks of length 0. We never actually split off any chunks, not even from an empty string, so this takes forever.

Note that gs2 doesn't have any traditional looping constructs.

(Mitch Schwartz found this and told me about it, and I thought it was a really cute feature.)

Answer 24

Whitespace, 9 bytes

;
...; create label [space]
;
.;
.    goto label [space]

. represents a space and ; represents a newline character.

Answer 25

RoboTalk, 5 bytes

0 rti

RoboTalk has three "goto" instructions: jump, return, and rti. Jump and return are plain "go to the address on the top of the stack" instructions, while rti has the side effect of (re-)enabling interrupts, as it's intended to be used to exit interrupt handlers. In a robot without any interrupt handlers defined, however, it is functionally equivalent to the other two instructions while being one byte shorter than jump.

Answer 26

FlogScript, 2 bytes

F<

The F< (flow-control-restart) command repeatedly restarts the program.

Answer 27

Groovy, 8 bytes

for(;;);

Shortened from the original thanks to suggestions. The trailing semicolon is still required, unfortunately.

while(1){}

Answer 28

Factor, 14 bytes

: a ( -- ) a ;

and nicely symmetrical looking (almost)

Answer 29

8085 Intel Microprocessor ,4 1 byte

0000h: pchl

whose machine code is:

E9

Just reset the microprocessor. And load E9 at 0000h.

p.s: its almost impossible in some kit to load program at ROM memory(which is basically the start memory) So, it works on simulator and some special kits only.

C000H: lxi h,C000h
C003H: pchl

whose machine code will be

21 00 0C E9 

loaded in memory from C000H

Answer 30

Pyth, 3 bytes

W1 

Note that there is a space after W1.