1475882 - Enable more clang-tidy/clang-analyzer checks

Status: RESOLVED FIXED

(Developer Infrastructure :: Source Code Analysis, defect, P3)

Description

[Chris Peterson [:cpeterson]]

These checks have few or no warnings in mozilla-central. :D

See https://clang-analyzer.llvm.org/available_checks.html for more info on the following checks:

clang-analyzer-cplusplus.NewDelete
clang-analyzer-cplusplus.NewDeleteLeaks
clang-analyzer-unix.cstring.BadSizeArg
clang-analyzer-unix.cstring.NullArg
clang-analyzer-unix.Malloc

See https://clang.llvm.org/extra/clang-tidy/checks/list.html for more info on the following checks:

bugprone-suspicious-memset-usage
misc-macro-repeated-side-effects
misc-string-constructor
misc-string-integer-assignment
misc-swapped-arguments
misc-unused-alias-decls

Comment 1

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - Enable clang-tidy's clang-analyzer-cplusplus.NewDelete check.

Check for double-free, use-after-free and offset problems involving C++ delete. There are currently no clang-analyzer-cplusplus.NewDelete warnings in mozilla-central!

https://clang-analyzer.llvm.org/available_checks.html

Review commit: https://reviewboard.mozilla.org/r/257076/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257076/

Comment 2

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - Enable clang-tidy's clang-analyzer-cplusplus.NewDeleteLeaks check.

Check for memory leaks. Traces memory managed by new/ delete. There are currently no clang-analyzer-cplusplus.NewDeleteLeaks warnings in mozilla-central!

https://clang-analyzer.llvm.org/available_checks.html

Review commit: https://reviewboard.mozilla.org/r/257078/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257078/

Comment 3

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.BadSizeArg check.

Check the size argument passed to strncat for common erroneous patterns. There are currently no clang-analyzer-unix.cstring.BadSizeArg warnings in mozilla-central!

https://clang-analyzer.llvm.org/available_checks.html

Review commit: https://reviewboard.mozilla.org/r/257080/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257080/

Comment 4

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.NullArg check.

Check for null pointers being passed as arguments to C string functions. There are no clang-analyzer-unix.cstring.NullArg warnings in mozilla-central!

strlen
strnlen
strcpy
strncpy
strcat
strncat
strcmp
strncmp
strcasecmp
strncasecmp

https://clang-analyzer.llvm.org/available_checks.html

Review commit: https://reviewboard.mozilla.org/r/257082/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257082/

Comment 5

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.Malloc check.

Check for memory leaks, double free, and use-after-free and offset problems involving malloc. There are currently no clang-analyzer-unix.Malloc warnings in mozilla-central!

https://clang-analyzer.llvm.org/available_checks.html

Review commit: https://reviewboard.mozilla.org/r/257084/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257084/

Comment 6

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - clang-tidy: Enable bugprone-suspicious-memset-usage check.

This check finds memset() calls with potential mistakes in their arguments. There are currently no bugprone-suspicious-memset-usage warnings in mozilla-central!

https://clang.llvm.org/extra/clang-tidy/checks/bugprone-suspicious-memset-usage.html

Review commit: https://reviewboard.mozilla.org/r/257086/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257086/

Comment 7

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - Enable clang-tidy's misc-macro-repeated-side-effects check.

This check finds side effects from repeated macro arguments:

https://clang.llvm.org/extra/clang-tidy/checks/bugprone-macro-repeated-side-effects.html

There are currently 16 misc-macro-repeated-side-effects warnings in mozilla-central, but they are all in third-party gfx/cairo code:

gfx/cairo/cairo/src/cairo-tor-scan-converter.c:1432:10: warning: side effects in the 1st macro argument 'x' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1011:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1037:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1062:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1088:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1107:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1126:27: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1194:21: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:1258:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:600:28: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:629:28: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:660:28: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:690:28: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:721:28: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-access.c:986:16: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion
gfx/cairo/libpixman/src/pixman-edge-imp.h:126:20: warning: side effects in the 2nd macro argument 'ptr' are repeated in macro expansion

Review commit: https://reviewboard.mozilla.org/r/257088/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257088/

Comment 8

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - clang-tidy: Enable misc-string-constructor check.

Finds string constructors that are suspicious and probably errors. There are currently no misc-string-constructor warnings in mozilla-central!

https://clang.llvm.org/extra/clang-tidy/checks/bugprone-string-constructor.html

Review commit: https://reviewboard.mozilla.org/r/257090/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257090/

Comment 9

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - clang-tidy: Enable misc-string-integer-assignment check.

The check finds assignments of an integer to std::string:

https://clang.llvm.org/extra/clang-tidy/checks/bugprone-string-integer-assignment.html

There are currently ten misc-string-integer-assignment warnings in mozilla-central, but they are all in third-party Breakpad code:

toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:306:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:307:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:309:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:310:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:311:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:313:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:314:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:315:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility
toolkit/crashreporter/google-breakpad/src/processor/minidump.cc:316:17: warning: an integer is interpreted as a character code when assigning it to a string; if this is intended, cast the integer to the appropriate character type; if you want a string representation, use the appropriate conversion facility

Review commit: https://reviewboard.mozilla.org/r/257092/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257092/

Comment 10

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - Enable clang-tidy's misc-swapped-arguments check.

This check finds potentially swapped function arguments by looking at implicit conversions. There are currently no misc-swapped-arguments warnings in mozilla-central!

https://clang.llvm.org/extra/clang-tidy/checks/bugprone-swapped-arguments.html

Review commit: https://reviewboard.mozilla.org/r/257094/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257094/

Comment 11

[Chris Peterson [:cpeterson]]

Attachment: Bug 1475882 - Enable clang-tidy's misc-unused-alias-decls check.

This check finds unused namespace alias declarations. There are currently no misc-unused-alias-decls warnings in mozilla-central!

https://clang.llvm.org/extra/clang-tidy/checks/misc-unused-alias-decls.html

Review commit: https://reviewboard.mozilla.org/r/257096/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/257096/

Comment 12

[Andi [:andi]]

Comment on attachment 8992246 [details]
Bug 1475882 - Enable clang-tidy's clang-analyzer-cplusplus.NewDelete check.

https://reviewboard.mozilla.org/r/257076/#review263968

Thank you!

Comment 13

[Andi [:andi]]

I'm gonna run these patches also on automation to make sure nothing boogie is happening: https://treeherder.mozilla.org/#/jobs?repo=try&revision=e87c1e134645010667310e312fed69266994ac17

Comment 14

[Sylvestre Ledru [:Sylvestre]]

Comment on attachment 8992246 [details]
Bug 1475882 - Enable clang-tidy's clang-analyzer-cplusplus.NewDelete check.

https://reviewboard.mozilla.org/r/257076/#review263972

::: commit-message-6a320:1
(Diff revision 1)
> +Bug 1475882 - Enable clang-tidy's clang-analyzer-cplusplus.NewDelete check. r?andi

I know I am bikesheding but this isn't a clang-tidy checker but clang-analyzer. :)

(different architecture and upstream)

Comment 15

[Andi [:andi]]

Comment on attachment 8992247 [details]
Bug 1475882 - Enable clang-tidy's clang-analyzer-cplusplus.NewDeleteLeaks check.

https://reviewboard.mozilla.org/r/257078/#review264014

As Sylvestre said earlier this is a clang analyzer checker, even if it's used through clang-tidy interface.

Comment 16

[Andi [:andi]]

Comment on attachment 8992248 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.BadSizeArg check.

https://reviewboard.mozilla.org/r/257080/#review264036

::: tools/clang-tidy/test/clang-analyzer-unix.cstring.BadSizeArg.cpp:4
(Diff revision 1)
> +// https://clang-analyzer.llvm.org/available_checks.html
> +
> +#include <string.h>
> +

Please see how clang-analyzer-security.insecureAPI.mktemp test is implemented. We don't really want here to include system headers but to declare de signature for each function that we call.

Comment 17

[Andi [:andi]]

Comment on attachment 8992249 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.NullArg check.

https://reviewboard.mozilla.org/r/257082/#review264048

::: tools/clang-tidy/test/clang-analyzer-unix.cstring.NullArg.cpp:4
(Diff revision 1)
> +// https://clang-analyzer.llvm.org/available_checks.html
> +
> +#include <string.h>
> +

Same comments as per my previous review, you can do something similar to this: 
https://treeherder.mozilla.org/#/jobs?repo=try&revision=6b15d6904a5f62c9085f5ed9b6b032093f3b5d08&selectedJob=188367458
Ofcourse including stren declaration in structures.h.

Comment 18

[Andi [:andi]]

Comment on attachment 8992250 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.Malloc check.

https://reviewboard.mozilla.org/r/257084/#review264066

::: tools/clang-tidy/test/clang-analyzer-unix.Malloc.cpp:4
(Diff revision 1)
> +// https://clang-analyzer.llvm.org/available_checks.html
> +
> +#include <stdlib.h>
> +

As per previous comments, let's do something like this please: https://treeherder.mozilla.org/#/jobs?repo=try&revision=152544ed0b689e695be95fe75b2f5fafac7ddbba

Comment 19

[Andi [:andi]]

Comment on attachment 8992251 [details]
Bug 1475882 - clang-tidy: Enable bugprone-suspicious-memset-usage check.

https://reviewboard.mozilla.org/r/257086/#review264068

::: tools/clang-tidy/test/bugprone-suspicious-memset-usage.cpp:4
(Diff revision 1)
> +// https://clang.llvm.org/extra/clang-tidy/checks/bugprone-suspicious-memset-usage.html
> +
> +#include <string.h>
> +

Let's use the official test uit for this checker: https://github.com/llvm-mirror/clang-tools-extra/blob/release_50/test/clang-tidy/bugprone-suspicious-memset-usage.cpp or just declare:

void *memset(void *, int, __SIZE_TYPE__);

Comment 20

[Andi [:andi]]

Comment on attachment 8992252 [details]
Bug 1475882 - Enable clang-tidy's misc-macro-repeated-side-effects check.

https://reviewboard.mozilla.org/r/257088/#review264072

thank you!

Comment 21

[Andi [:andi]]

Comment on attachment 8992253 [details]
Bug 1475882 - clang-tidy: Enable misc-string-constructor check.

https://reviewboard.mozilla.org/r/257090/#review264074

::: tools/clang-tidy/test/misc-string-constructor.cpp:4
(Diff revision 1)
> +// https://clang.llvm.org/extra/clang-tidy/checks/bugprone-string-constructor.html
> +
> +#include <string>
> +

As per previous remarks, let's not include please <string> and let's declare our container, for example:

https://github.com/Microsoft/clang-tools-extra/blob/master/test/clang-tidy/misc-string-constructor.cpp

Comment 22

[Andi [:andi]]

Comment on attachment 8992254 [details]
Bug 1475882 - clang-tidy: Enable misc-string-integer-assignment check.

https://reviewboard.mozilla.org/r/257092/#review264078

::: tools/clang-tidy/test/misc-string-integer-assignment.cpp:4
(Diff revision 1)
> +// https://clang.llvm.org/extra/clang-tidy/checks/bugprone-string-integer-assignment.html
> +
> +#include <string>
> +

Same applies here regarding the string container, https://github.com/llvm-mirror/clang-tools-extra/blob/release_50/test/clang-tidy/misc-string-integer-assignment.cpp

Comment 23

[Andi [:andi]]

Comment on attachment 8992255 [details]
Bug 1475882 - Enable clang-tidy's misc-swapped-arguments check.

https://reviewboard.mozilla.org/r/257094/#review264080

Thank you!

Comment 24

[Andi [:andi]]

Comment on attachment 8992256 [details]
Bug 1475882 - Enable clang-tidy's misc-unused-alias-decls check.

https://reviewboard.mozilla.org/r/257096/#review264082

Comment 25

[Chris Peterson [:cpeterson]]

Thanks! I'll fix the clang-analyzer commit messages and add the function prototypes to structures.h instead of #including system header files.

Comment 26

[Chris Peterson [:cpeterson]]

Comment on attachment 8992248 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.BadSizeArg check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257080/diff/1-2/

Comment 27

[Chris Peterson [:cpeterson]]

Comment on attachment 8992249 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.NullArg check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257082/diff/1-2/

Comment 28

[Chris Peterson [:cpeterson]]

Comment on attachment 8992250 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.Malloc check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257084/diff/1-2/

Comment 29

[Chris Peterson [:cpeterson]]

Comment on attachment 8992251 [details]
Bug 1475882 - clang-tidy: Enable bugprone-suspicious-memset-usage check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257086/diff/1-2/

Comment 30

[Chris Peterson [:cpeterson]]

Comment on attachment 8992252 [details]
Bug 1475882 - Enable clang-tidy's misc-macro-repeated-side-effects check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257088/diff/1-2/

Comment 31

[Chris Peterson [:cpeterson]]

Comment on attachment 8992253 [details]
Bug 1475882 - clang-tidy: Enable misc-string-constructor check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257090/diff/1-2/

Comment 32

[Chris Peterson [:cpeterson]]

Comment on attachment 8992254 [details]
Bug 1475882 - clang-tidy: Enable misc-string-integer-assignment check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257092/diff/1-2/

Comment 33

[Chris Peterson [:cpeterson]]

Comment on attachment 8992255 [details]
Bug 1475882 - Enable clang-tidy's misc-swapped-arguments check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257094/diff/1-2/

Comment 34

[Chris Peterson [:cpeterson]]

Comment on attachment 8992256 [details]
Bug 1475882 - Enable clang-tidy's misc-unused-alias-decls check.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/257096/diff/1-2/

Comment 35

[Chris Peterson [:cpeterson]]

Here is a green static-analysis autotest with my fixes on Try:

https://treeherder.mozilla.org/#/jobs?repo=try&revision=1d54e6995143bf4e4acaae4ef32661a746ede538

Comment 36

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/138f27a016f6
clang-analyzer: Enable clang-analyzer-cplusplus.NewDelete check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/082c2cd47f1c
clang-analyzer: Enable clang-analyzer-cplusplus.NewDeleteLeaks check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/6a5e540c17f3
clang-tidy: Enable misc-macro-repeated-side-effects check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/191a529a0208
clang-tidy: Enable misc-swapped-arguments check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/13739445a00b
clang-tidy: Enable misc-unused-alias-decls check. r=andi

Comment 37

[Andi [:andi]]

Comment on attachment 8992254 [details]
Bug 1475882 - clang-tidy: Enable misc-string-integer-assignment check.

https://reviewboard.mozilla.org/r/257092/#review264482

Comment 38

[Andi [:andi]]

Comment on attachment 8992253 [details]
Bug 1475882 - clang-tidy: Enable misc-string-constructor check.

https://reviewboard.mozilla.org/r/257090/#review264484

Comment 39

[Andi [:andi]]

Comment on attachment 8992248 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.BadSizeArg check.

https://reviewboard.mozilla.org/r/257080/#review264486

Comment 40

[Andi [:andi]]

Comment on attachment 8992249 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.cstring.NullArg check.

https://reviewboard.mozilla.org/r/257082/#review264488

Comment 41

[Andi [:andi]]

Comment on attachment 8992250 [details]
Bug 1475882 - clang-analyzer: Enable clang-analyzer-unix.Malloc check.

https://reviewboard.mozilla.org/r/257084/#review264490

Comment 42

[Andi [:andi]]

Comment on attachment 8992251 [details]
Bug 1475882 - clang-tidy: Enable bugprone-suspicious-memset-usage check.

https://reviewboard.mozilla.org/r/257086/#review264492

Comment 43

[Andi [:andi]]

(In reply to Chris Peterson [:cpeterson] from comment #35)
> Here is a green static-analysis autotest with my fixes on Try:
> 
> https://treeherder.mozilla.org/#/
> jobs?repo=try&revision=1d54e6995143bf4e4acaae4ef32661a746ede538
Thank you very much for doing this!

Comment 44

[Tiberius Oros[:tiberius_oros]]

https://hg.mozilla.org/mozilla-central/rev/138f27a016f6
https://hg.mozilla.org/mozilla-central/rev/082c2cd47f1c
https://hg.mozilla.org/mozilla-central/rev/6a5e540c17f3
https://hg.mozilla.org/mozilla-central/rev/191a529a0208
https://hg.mozilla.org/mozilla-central/rev/13739445a00b

Comment 45

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/21408667426c
clang-analyzer: Enable clang-analyzer-unix.cstring.BadSizeArg check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/8a9e7ed36126
clang-analyzer: Enable clang-analyzer-unix.cstring.NullArg check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/f6ee4608a559
clang-analyzer: Enable clang-analyzer-unix.Malloc check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/be36725735f0
clang-tidy: Enable bugprone-suspicious-memset-usage check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/ffa7c88ba619
clang-tidy: Enable misc-string-constructor check. r=andi
https://hg.mozilla.org/integration/mozilla-inbound/rev/3a3725565d12
clang-tidy: Enable misc-string-integer-assignment check. r=andi

Comment 46

[Eliza Balazs [:ebalazs_]]

https://hg.mozilla.org/mozilla-central/rev/21408667426c
https://hg.mozilla.org/mozilla-central/rev/8a9e7ed36126
https://hg.mozilla.org/mozilla-central/rev/f6ee4608a559
https://hg.mozilla.org/mozilla-central/rev/be36725735f0
https://hg.mozilla.org/mozilla-central/rev/ffa7c88ba619
https://hg.mozilla.org/mozilla-central/rev/3a3725565d12