[clang] [Modules] Fix using `va_list` with modules and a precompiled header. (PR #100837)

Fri Aug 2 08:51:02 PDT 2024

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-armv8-quick` running on `linaro-clang-armv8-quick` while building `clang` at step 5 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/154/builds/2288

Here is the relevant piece of the build log for the reference:
```
Step 5 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'Clang :: Modules/builtin-vararg.c' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 3: rm -rf /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp
+ rm -rf /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp
RUN: at line 4: split-file /home/tcwg-buildbot/worker/clang-armv8-quick/llvm/clang/test/Modules/builtin-vararg.c /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp
+ split-file /home/tcwg-buildbot/worker/clang-armv8-quick/llvm/clang/test/Modules/builtin-vararg.c /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp
RUN: at line 6: /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/bin/clang -cc1 -internal-isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/lib/clang/20/include -nostdsysteminc -triple x86_64-apple-darwin    -fmodules -fno-implicit-modules -fbuiltin-headers-in-system-modules    -emit-module -fmodule-name=DeclareVarargs    -x c /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include/module.modulemap -o /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/DeclareVarargs.pcm    -fmodule-map-file=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/resource_dir/module.modulemap -isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/resource_dir
+ /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/bin/clang -cc1 -internal-isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/lib/clang/20/include -nostdsysteminc -triple x86_64-apple-darwin -fmodules -fno-implicit-modules -fbuiltin-headers-in-system-modules -emit-module -fmodule-name=DeclareVarargs -x c /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include/module.modulemap -o /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/DeclareVarargs.pcm -fmodule-map-file=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/resource_dir/module.modulemap -isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/resource_dir
RUN: at line 11: /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/bin/clang -cc1 -internal-isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/lib/clang/20/include -nostdsysteminc -triple x86_64-apple-darwin    -fmodules -fno-implicit-modules -fbuiltin-headers-in-system-modules    -emit-pch -fmodule-name=Prefix    -x c-header /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/prefix.pch -o /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/prefix.pch.gch    -fmodule-map-file=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include/module.modulemap -fmodule-file=DeclareVarargs=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/DeclareVarargs.pcm    -I /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include
+ /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/bin/clang -cc1 -internal-isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/lib/clang/20/include -nostdsysteminc -triple x86_64-apple-darwin -fmodules -fno-implicit-modules -fbuiltin-headers-in-system-modules -emit-pch -fmodule-name=Prefix -x c-header /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/prefix.pch -o /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/prefix.pch.gch -fmodule-map-file=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include/module.modulemap -fmodule-file=DeclareVarargs=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/DeclareVarargs.pcm -I /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include
RUN: at line 17: /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/bin/clang -cc1 -internal-isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/lib/clang/20/include -nostdsysteminc -triple x86_64-apple-darwin    -fmodules -fno-implicit-modules -fbuiltin-headers-in-system-modules    -emit-obj -fmodule-name=test    -x c /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/test.c -o /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/test.o    -Werror=incompatible-pointer-types    -fmodule-file=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/DeclareVarargs.pcm -include-pch /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/prefix.pch.gch    -I /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include
+ /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/bin/clang -cc1 -internal-isystem /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/lib/clang/20/include -nostdsysteminc -triple x86_64-apple-darwin -fmodules -fno-implicit-modules -fbuiltin-headers-in-system-modules -emit-obj -fmodule-name=test -x c /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/test.c -o /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/test.o -Werror=incompatible-pointer-types -fmodule-file=/home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/DeclareVarargs.pcm -include-pch /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/prefix.pch.gch -I /home/tcwg-buildbot/worker/clang-armv8-quick/stage1/tools/clang/test/Modules/Output/builtin-vararg.c.tmp/include
error: unable to create target: 'No available targets are compatible with triple "x86_64-apple-darwin"'
1 error generated.

--

********************

```

https://github.com/llvm/llvm-project/pull/100837