Thread: PostgreSQL does not compile on macOS SDK 15.0

Xcode 16 beta was released on 2024-06-10 and ships with macOS SDK 15.0
[1]. It appears PostgreSQL does not compile due to typedef redefiniton
errors in the regex library:

/tmp/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
-Wall -Wmissing-prototypes -Wpointer-arith
-Wdeclaration-after-statement -Werror=vla
-Werror=unguarded-availability-new -Wendif-labels
-Wmissing-format-attribute -Wcast-function-type -Wformat-security
-fno-strict-aliasing -fwrapv -fexcess-precision=standard
-Wno-unused-command-line-argument -Wno-compound-token-split-by-macro
-Wno-cast-function-type-strict -O2 -I../../../src/include  -isysroot
/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk
   -c -o regcomp.o regcomp.c
In file included from regcomp.c:2647:
In file included from ./regc_pg_locale.c:21:
In file included from ../../../src/include/utils/pg_locale.h:16:
In file included from

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale.h:45:
In file included from

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale/_regex.h:27:

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/_regex.h:107:24:
error: typedef redefinition with different types ('__darwin_off_t'
(aka 'long long') vs 'long')
  107 | typedef __darwin_off_t regoff_t;
      |                        ^
../../../src/include/regex/regex.h:48:14: note: previous definition is here
   48 | typedef long regoff_t;
      |              ^
In file included from regcomp.c:2647:
In file included from ./regc_pg_locale.c:21:
In file included from ../../../src/include/utils/pg_locale.h:16:
In file included from

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale.h:45:
In file included from

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale/_regex.h:27:

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/_regex.h:114:3:
error: typedef redefinition with different types ('struct regex_t' vs
'struct regex_t')
  114 | } regex_t;
      |   ^
../../../src/include/regex/regex.h:82:3: note: previous definition is here
   82 | } regex_t;
      |   ^
In file included from regcomp.c:2647:
In file included from ./regc_pg_locale.c:21:
In file included from ../../../src/include/utils/pg_locale.h:16:
In file included from

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale.h:45:
In file included from

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale/_regex.h:27:

/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/_regex.h:119:3:
error: typedef redefinition with different types ('struct regmatch_t'
vs 'struct regmatch_t')
  119 | } regmatch_t;
      |   ^
../../../src/include/regex/regex.h:89:3: note: previous definition is here
   89 | } regmatch_t;
      |   ^
3 errors generated.
make[3]: *** [regcomp.o] Error 1
make[2]: *** [regex-recursive] Error 2
make[1]: *** [all-backend-recurse] Error 2
make: *** [all-src-recurse] Error 2

I've reproduced this issue by:

1. Download the XCode 16 beta 2 ZIP file:
https://developer.apple.com/services-account/download?path=/Developer_Tools/Xcode_16_beta/Xcode_16_beta.xip
2. Extract this to `/tmp`.
3. Then I ran:

export PATH=/tmp/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin:$PATH
export SDKROOT=/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk
export XCODE_DIR=/tmp/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain
export CC="$XCODE_DIR/usr/bin/clang" export CXX="$XCODE_DIR/usr/bin/clang++"

./configure CC="$CC" CXX="$CXX"
make

The compilation goes through if I comment out the "#include
<xlocale/_regex.h>" from
/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk/usr/include/xlocale.h.
However, even on macOS SDK 14.5 I see that include statement. I'm
still trying to figure out what changed here.

[1] - https://developer.apple.com/macos/

Hi,

> I've reproduced this issue by:
>
> 1. Download the XCode 16 beta 2 ZIP file:
> https://developer.apple.com/services-account/download?path=/Developer_Tools/Xcode_16_beta/Xcode_16_beta.xip
> 2. Extract this to `/tmp`.
> 3. Then I ran:
>
> export PATH=/tmp/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin:$PATH
> export SDKROOT=/tmp/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.0.sdk
> export XCODE_DIR=/tmp/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain
> export CC="$XCODE_DIR/usr/bin/clang" export CXX="$XCODE_DIR/usr/bin/clang++"
>
> ./configure CC="$CC" CXX="$CXX"
> make

Does it work if you do the same with XCode 15?

Perhaps I'm missing something but to me it doesn't look like the
right/supported way of compiling PostgreSQL on this platform [1]. I
tried to figure out what version of Xcode I'm using right now, but it
seems to be none:

$ /usr/bin/xcodebuild -version
xcode-select: error: tool 'xcodebuild' requires Xcode, but active
developer directory '/Library/Developer/CommandLineTools' is a command
line tools instance

Clang I'm using doesn't seem to be part of XCode distribution either:

$ clang --version
Homebrew clang version 18.1.6
Target: x86_64-apple-darwin23.5.0
Thread model: posix
InstalledDir: /usr/local/opt/llvm/bin

It's been a while since I installed all the dependencies on my laptop,
but I'm pretty confident I followed the documentation back then.

IMO the right way to test PostgreSQL against the recent beta version
of MacOS SDK would be replacing (via a symlink perhaps) the SDK
provided by the "Command Line Tools for Xcode" package
(/Library/Developer/CommandLineTools/SDKs/). Or alternatively finding
the official way of installing the beta version of this package.

[1]: https://www.postgresql.org/docs/current/installation-platform-notes.html#INSTALLATION-NOTES-MACOS

-- 
Best regards,
Aleksander Alekseev

Hi,

> IMO the right way to test PostgreSQL against the recent beta version
> of MacOS SDK would be replacing (via a symlink perhaps) the SDK
> provided by the "Command Line Tools for Xcode" package
> (/Library/Developer/CommandLineTools/SDKs/). Or alternatively finding
> the official way of installing the beta version of this package.

As it turned out there is Command_Line_Tools_for_Xcode_16_beta.dmg
package available. It can be downloaded from
https://developer.apple.com/ after logging it. I installed it and also
did:

```
cd /Library/Developer/CommandLineTools/SDKs
sudo mkdir __ignore__
sudo mv MacOSX14.* __ignore__
```

... to make sure Postgres will not find the older version of SDK (it
did until I made this step).

Now I get the following output from `meson --setup ...`:

```
The Meson build system
Version: 0.61.2
Source dir: /Users/eax/projects/c/postgresql
Build dir: /Users/eax/projects/c/postgresql/build
Build type: native build
Project name: postgresql
Project version: 17beta2
C compiler for the host machine: cc (clang 16.0.0 "Apple clang version
16.0.0 (clang-1600.0.20.10)")
C linker for the host machine: cc ld64 1115.5.3
Host machine cpu family: x86_64
Host machine cpu: x86_64
Run-time dependency threads found: YES
Message: darwin sysroot: /Library/Developer/CommandLineTools/SDKs/MacOSX15.0.sdk
...
```

... and get the error reported by Stan. Also I can confirm that the
proposed workaround fixes it. Attached is the result of `git
format-patch` for convenience.

Personally I'm not extremely happy with this workaround though. An
alternative solution would be adding the "pg_" prefix to our type
declarations.

Another question is whether we should fix this while the SDK is in
beta or only after it is released.

Thoughts?

I added the patch to the nearest commitfest so that it wouldn't be lost [1].

[1]: https://commitfest.postgresql.org/48/5073/

-- 
Best regards,
Aleksander Alekseev

Hi,

On 2024-06-25 16:49:32 +0300, Aleksander Alekseev wrote:
> ... to make sure Postgres will not find the older version of SDK (it
> did until I made this step).

You should be able to influence that by specifying -Ddarwin_sysroot=...


> ... and get the error reported by Stan. Also I can confirm that the
> proposed workaround fixes it. Attached is the result of `git
> format-patch` for convenience.
> 
> Personally I'm not extremely happy with this workaround though.

Yea, it seems decidedly not great.


> An alternative solution would be adding the "pg_" prefix to our type
> declarations.

A third approach would be to make sure we don't include xlocale.h from
pg_locale.h.  IMO pg_locale currently exposes too many implementation details,
neither xlocale.h nor ucol.h should be included in it, that should be in a C
file.


> Another question is whether we should fix this while the SDK is in
> beta or only after it is released.

Yea.

Greetings,

Andres Freund

Andres Freund <andres@anarazel.de> writes:
> On 2024-06-25 16:49:32 +0300, Aleksander Alekseev wrote:
>> Another question is whether we should fix this while the SDK is in
>> beta or only after it is released.

> Yea.

Stan has started multiple threads about this, which is not doing
anyone any favors, but that issue was already brought up in

https://www.postgresql.org/message-id/flat/4edd2d3c30429c4445cc805ae9a788c489856eb7.1719265762.git.stanhu%40gmail.com

I think the immediate action item should be to push back on the
change and see if we can get Apple to undo it.  If we have to
fix it on our side, it is likely to involve API-breaking changes
that will cause trouble for extensions.  The more so because
we'll have to change stable branches too.

I tend to agree with the idea that not including <xlocale.h>
so widely might be the least-bad fix; but that still risks
breaking code that was dependent on that inclusion.

            regards, tom lane

Thanks, everyone. Sorry to create multiple threads on this.

As I mentioned in the other thread, I've already submitted a bug
report to Apple (FB14047412). My colleagues know a key macOS engineer,
and they have reached out to him to review that thread and bug report.
I'll update if we hear anything.

On Tue, Jun 25, 2024 at 7:39 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> Andres Freund <andres@anarazel.de> writes:
> > On 2024-06-25 16:49:32 +0300, Aleksander Alekseev wrote:
> >> Another question is whether we should fix this while the SDK is in
> >> beta or only after it is released.
>
> > Yea.
>
> Stan has started multiple threads about this, which is not doing
> anyone any favors, but that issue was already brought up in
>
> https://www.postgresql.org/message-id/flat/4edd2d3c30429c4445cc805ae9a788c489856eb7.1719265762.git.stanhu%40gmail.com
>
> I think the immediate action item should be to push back on the
> change and see if we can get Apple to undo it.  If we have to
> fix it on our side, it is likely to involve API-breaking changes
> that will cause trouble for extensions.  The more so because
> we'll have to change stable branches too.
>
> I tend to agree with the idea that not including <xlocale.h>
> so widely might be the least-bad fix; but that still risks
> breaking code that was dependent on that inclusion.
>
>                         regards, tom lane