[BUG] Git 2.41.0-rc0 - Compile Error ALLOC_GROW

> Hi Git Team,
>
> I am getting a compile error on rc0:
>
>   	ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1,
> git_atexit_hdlrs.alloc);
>   	^
> "/home/ituglib/randall/jenkins/.jenkins/workspace/Git_Pipeline/run-command.c
> ", line 1103: error(114): identifier "ALLOC_GROW" is undefined
>
> Any help o nthis?

>the macro.
>
>Signed-off-by: Junio C Hamano <gitster@pobox.com>
>
>---
> run-command.c | 1 +
> 1 file changed, 1 insertion(+)
>
>diff --git c/run-command.c w/run-command.c index d4247d5fcc..1affea48af

>--- c/run-command.c
>+++ w/run-command.c
>@@ -1073,6 +1073,7 @@ static void NORETURN async_exit(int code)  }
>
> #else
>+#include <alloc.h>
>
> static struct {
> 	void (**handlers)(void);

> On Tue, May 16, 2023 at 10:24:24AM -0700, Junio C Hamano wrote:
> > Recent header file shuffling missed this old user of ALLOC_GROW()
> > that was inside "#ifdef NO_PTHREADS' section and forgot to include
> > the new file, alloc.h, that defines the macro.
>
> Heh. I wrote an identical patch before lunch (which I just came back
> from). Feel free to queue either, I honestly do not care which as long
> as the bug is fixed :-).
>
>   https://lore.kernel.org/git/db403de74da839084165f11dab05d71484457c6f.1684259780.git.me@ttaylorr.com/

> OK, having now read both completely, I would say I have a vague
> preference for my version since it keeps the include at the top and
> unconditional, and has slightly more information in the patch message.
>
> But I do not prefer it so much over yours that I would be sad if you had
> already queued yours and didn't want to bother shuffling it around.

> Taylor Blau <me@ttaylorr.com> writes:
>
> > OK, having now read both completely, I would say I have a vague
> > preference for my version since it keeps the include at the top and
> > unconditional, and has slightly more information in the patch message.
> >
> > But I do not prefer it so much over yours that I would be sad if you had
> > already queued yours and didn't want to bother shuffling it around.
>
> I do not have much preference between the two, either.  Both lack
> one important description that we are reasonably confident that this
> breakage is limited to run-command.c and no other files.

> On Tue, May 16, 2023 at 11:44:36AM -0700, Junio C Hamano wrote:
>> Taylor Blau <me@ttaylorr.com> writes:
>>
>> > OK, having now read both completely, I would say I have a vague
>> > preference for my version since it keeps the include at the top and
>> > unconditional, and has slightly more information in the patch message.
>> >
>> > But I do not prefer it so much over yours that I would be sad if you had
>> > already queued yours and didn't want to bother shuffling it around.
>>
>> I do not have much preference between the two, either.  Both lack
>> one important description that we are reasonably confident that this
>> breakage is limited to run-command.c and no other files.
>
> I believe that mine does:
>
>   (Everything else compiles fine when NO_PTHREADS is defined, so this is
>   the only spot that needs fixing).

> When building git with `NO_PTHREADS=YesPlease`, we fail to build
> run-command.o since we don't have a definition for ALLOC_GROW:
>
>     $ make NO_PTHREADS=1 DEVELOPER=1 run-command.o
>     GIT_VERSION = 2.41.0.rc0.1.g787eb3beae.dirty
>         CC run-command.o
>     run-command.c: In function ‘git_atexit’:
>     run-command.c:1103:9: error: implicit declaration of function ‘ALLOC_GROW’ [-Werror=implicit-function-declaration]
>      1103 |         ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc);
>           |         ^~~~~~~~~~
>     cc1: all warnings being treated as errors
>     make: *** [Makefile:2715: run-command.o] Error 1

> We could fix this by conditionally including "alloc.h" when
> `NO_PTHREADS` is defined.  But we have relatively few examples of
> conditional includes throughout the tree[^1].
>
> Instead, include "alloc.h" unconditionally in run-command.c to allow it
> to successfully compile even when NO_PTHREADS is defined.

>Taylor Blau <me@ttaylorr.com> writes:
>
>> When building git with `NO_PTHREADS=YesPlease`, we fail to build
>> run-command.o since we don't have a definition for ALLOC_GROW:
>>
>>     $ make NO_PTHREADS=1 DEVELOPER=1 run-command.o
>>     GIT_VERSION = 2.41.0.rc0.1.g787eb3beae.dirty
>>         CC run-command.o
>>     run-command.c: In function ‘git_atexit’:
>>     run-command.c:1103:9: error: implicit declaration of function ‘ALLOC_GROW’ [-
>Werror=implicit-function-declaration]
>>      1103 |         ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1,
>git_atexit_hdlrs.alloc);
>>           |         ^~~~~~~~~~
>>     cc1: all warnings being treated as errors
>>     make: *** [Makefile:2715: run-command.o] Error 1
>
>I am OK to give a reproduction recipe, i.e. the "$ make" command line, to make it
>easy for people, who cannot remember how to define make variables from the
>command line, to try out themselves, but I hate the "build transcript" in the log
>message, when a few lines of prose suffices.
>
>How about this?
>
>    Git 2.41-rc0 fails to compile run-command.c with NO_PTHREADS
>    defined, i.e.
>
>      $ make NO_PTHREADS=1 run-command.o
>
>    as ALLOC_GROW() macro is used in the atexit() emulation but the
>    macro definition is not available.
>
>> This bisects to 36bf195890 (alloc.h: move ALLOC_GROW() functions from
>> cache.h, 2023-02-24), which replaced includes of "cache.h" with
>> "alloc.h", which is the new home of `ALLOC_GROW()` (and
>> `ALLOC_GROW_BY()`).
>
>Good.
>Insert something like:
>
>    We can see that run-command.c is the only one that try to use
>    these macros without including <alloc.h>.
>
>      $ git grep -l -e '[^_]ALLOC_GROW(' -e 'ALLOC_GROW_BY(' \*.c | sort >/tmp/1
>      $ git grep -l 'alloc\.h' \*.c | sort >/tmp/2
>      $ comm -23 /tmp/[12]
>      compat/simple-ipc/ipc-unix-socket.c
>      run-command.c
>
>    The "compat/" file only talks about the macro in the comment,
>    and is not broken.
>
>here.  What I am aiming for is to tell readers what they do not have to spend their
>time on.  As we encourage people to make sure to look for other errors that come
>from the same root cause when making a fix, avoiding duplicated work by telling
>what they do not have to look at is rather important.
>
>> run-command.c compiles fine when `NO_PTHREADS` is undefined, since its
>> use of `ALLOC_GROW()` is behind a `#ifndef NO_PTHREADS`. (Everything
>> else compiles fine when NO_PTHREADS is defined, so this is the only
>> spot that needs fixing).
>
>I think we can say that, but is probably coered by the three-line summary I gave
>above.
>
>> We could fix this by conditionally including "alloc.h" when
>> `NO_PTHREADS` is defined.  But we have relatively few examples of
>> conditional includes throughout the tree[^1].
>>
>> Instead, include "alloc.h" unconditionally in run-command.c to allow
>> it to successfully compile even when NO_PTHREADS is defined.
>
>Good.
>
>> [^1]: With `git grep -E -A1 '#if(n)?def' -- **/*.c | grep '#include' -B1`.
>
>Good.

> Taylor Blau <me@ttaylorr.com> writes:
>
> > When building git with `NO_PTHREADS=YesPlease`, we fail to build
> > run-command.o since we don't have a definition for ALLOC_GROW:
> >
> >     $ make NO_PTHREADS=1 DEVELOPER=1 run-command.o
> >     GIT_VERSION = 2.41.0.rc0.1.g787eb3beae.dirty
> >         CC run-command.o
> >     run-command.c: In function ‘git_atexit’:
> >     run-command.c:1103:9: error: implicit declaration of function ‘ALLOC_GROW’ [-Werror=implicit-function-declaration]
> >      1103 |         ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc);
> >           |         ^~~~~~~~~~
> >     cc1: all warnings being treated as errors
> >     make: *** [Makefile:2715: run-command.o] Error 1
>
> I am OK to give a reproduction recipe, i.e. the "$ make" command
> line, to make it easy for people, who cannot remember how to define
> make variables from the command line, to try out themselves, but I
> hate the "build transcript" in the log message, when a few lines of
> prose suffices.

>
> On Tue, May 16, 2023 at 12:12:02PM -0700, Junio C Hamano wrote:
> > Taylor Blau <me@ttaylorr.com> writes:
> >
> > > When building git with `NO_PTHREADS=YesPlease`, we fail to build
> > > run-command.o since we don't have a definition for ALLOC_GROW:
> > >
> > >     $ make NO_PTHREADS=1 DEVELOPER=1 run-command.o
> > >     GIT_VERSION = 2.41.0.rc0.1.g787eb3beae.dirty
> > >         CC run-command.o
> > >     run-command.c: In function ‘git_atexit’:
> > >     run-command.c:1103:9: error: implicit declaration of function ‘ALLOC_GROW’ [-Werror=implicit-function-declaration]
> > >      1103 |         ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc);
> > >           |         ^~~~~~~~~~
> > >     cc1: all warnings being treated as errors
> > >     make: *** [Makefile:2715: run-command.o] Error 1
> >
> > I am OK to give a reproduction recipe, i.e. the "$ make" command
> > line, to make it easy for people, who cannot remember how to define
> > make variables from the command line, to try out themselves, but I
> > hate the "build transcript" in the log message, when a few lines of
> > prose suffices.
>
> Much appreciated. Here's a version with your changes include that is
> suitable for queueing:
>
> --- 8< ---
>
> Subject: [PATCH] run-command.c: fix missing include under `NO_PTHREADS`
>
> Git 2.41-rc0 fails to compile run-command.c with `NO_PTHREADS` defined,
> i.e.
>
>   $ make NO_PTHREADS=1 run-command.o
>
> as `ALLOC_GROW()` macro is used in the `atexit()` emulation but the
> macro definition is not available.
>
> This bisects to 36bf195890 (alloc.h: move ALLOC_GROW() functions from
> cache.h, 2023-02-24), which replaced includes of <cache.h> with
> <alloc.h>, which is the new home of `ALLOC_GROW()` (and
> `ALLOC_GROW_BY()`).
>
> We can see that run-command.c is the only one that try to use these
> macros without including <alloc.h>.
>
>   $ git grep -l -e '[^_]ALLOC_GROW(' -e 'ALLOC_GROW_BY(' \*.c | sort >/tmp/1
>   $ git grep -l 'alloc\.h' \*.c | sort >/tmp/2
>   $ comm -23 /tmp/[12]
>   compat/simple-ipc/ipc-unix-socket.c
>   run-command.c
>
> The "compat/" file only talks about the macro in the comment,
> and is not broken.
>
> We could fix this by conditionally including "alloc.h" when
> `NO_PTHREADS` is defined.  But we have relatively few examples of
> conditional includes throughout the tree[^1].
>
> Instead, include "alloc.h" unconditionally in run-command.c to allow it
> to successfully compile even when NO_PTHREADS is defined.
>
> [^1]: With `git grep -E -A1 '#if(n)?def' -- **/*.c | grep '#include' -B1`.
>
> Reported-by: Randall S. Becker <randall.becker@nexbridge.ca>
> Co-authored-by: Junio C Hamano <gitster@pobox.com>
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
> Signed-off-by: Taylor Blau <me@ttaylorr.com>
> ---
>  run-command.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/run-command.c b/run-command.c
> index d4247d5fcc..60c9419866 100644
> --- a/run-command.c
> +++ b/run-command.c
> @@ -16,6 +16,7 @@
>  #include "packfile.h"
>  #include "hook.h"
>  #include "compat/nonblock.h"
> +#include "alloc.h"
>
>  void child_process_init(struct child_process *child)
>  {
> --
> 2.41.0.rc0.dirty