From a31ad0492f02fb55693f2306ab5693985de560d7 Mon Sep 17 00:00:00 2001
From: Andres Freund <andres@anarazel.de>
Date: Tue, 9 Jun 2026 10:18:50 -0400
Subject: [PATCH v13a 2/9] ci: Use meson for most of CompilerWarnings, it's a
 lot faster

Previously, with a cold cache or a change in a central header, the
CompilerWarnings job would take ~35 minutes. The worst aspect of that was the
windows cross build, which would take about 8-10 minutes.

Migrate the compiler warnings tasks to meson, that generally makes the
cold-cache build a bit faster, and makes the windows cross build a *lot*
faster, due to being able to use precompiled headers.

With that the cold cache performance improves to about 12 minutes.

Discussion: https://postgr.es/m/a2ejn7lfqolutzz7kozalbhy3bixdrujb4buc3pgbtlk4am2ba@wbv6v7riia33
---
 .github/workflows/pg-ci.yml           | 38 +++++++++++++--------------
 src/tools/ci/meson-cross-w64-ucrt.txt | 21 +++++++++++++++
 2 files changed, 40 insertions(+), 19 deletions(-)
 create mode 100644 src/tools/ci/meson-cross-w64-ucrt.txt

diff --git a/.github/workflows/pg-ci.yml b/.github/workflows/pg-ci.yml
index 742a8431782..81801800dac 100644
--- a/.github/workflows/pg-ci.yml
+++ b/.github/workflows/pg-ci.yml
@@ -1171,6 +1171,8 @@ jobs:
       # compilers / flag combinations.
       CCACHE_MAXSIZE: "1G"
       DEFAULT_BUILD: world-bin
+      CCACHE_SLOPPINESS: pch_defines,time_macros
+      CCACHE_DEPEND: 1
 
     steps:
       - *nix_sysinfo_step
@@ -1186,53 +1188,56 @@ jobs:
       - name: gcc warnings + (dtrace)
         if: ${{ !cancelled() }}
         env:
-          CONF: ${{env.LINUX_CONFIGURE_FEATURES}} --cache gcc.cache --enable-dtrace
+          CONF: ${{env.MESON_COMMON_FEATURES}} -Ddtrace=enabled
           CC: ccache gcc
           CXX: ccache g++
           CLANG: ccache clang
         run: &compiler_warnings_cmd |
           echo "::group::configure"
-          ./configure \
-            ${{env.CONF}} \
-            CLANG="ccache clang"
+          rm -rf build-meson
+          meson setup -Dwerror=true $CONF build-meson
           echo "::endgroup::"
 
-          make -s -j${{env.BUILD_JOBS}} clean
-          make -s -j${{env.BUILD_JOBS}} ${{env.DEFAULT_BUILD}}
+          ninja -C build-meson --quiet -j${{env.BUILD_JOBS}} ${{env.MBUILD_TARGET}}
 
       # gcc, cassert on, dtrace off
       - name: gcc warnings + (cassert)
         if: ${{ !cancelled() }}
         env:
-          CONF: ${{env.LINUX_CONFIGURE_FEATURES}} --cache gcc.cache --enable-cassert
+          CONF: ${{env.MESON_COMMON_FEATURES}} -Dcassert=true
           CC: ccache gcc
           CXX: ccache g++
+          CLANG: ccache clang
         run: *compiler_warnings_cmd
 
       # clang, cassert off, dtrace off
       - name: clang warnings
         if: ${{ !cancelled() }}
         env:
-          CONF: ${{env.LINUX_CONFIGURE_FEATURES}} --cache clang.cache
+          CONF: ${{env.MESON_COMMON_FEATURES}}
           CC: ccache clang
           CXX: ccache clang++
+          CLANG: ccache clang
         run: *compiler_warnings_cmd
 
       # clang, cassert on, dtrace on
       - name: clang warnings + (cassert + dtrace)
         if: ${{ !cancelled() }}
         env:
-          CONF: ${{env.LINUX_CONFIGURE_FEATURES}} --cache clang.cache --enable-cassert --enable-dtrace
+          CONF: ${{env.MESON_COMMON_FEATURES}} -Dcassert=true -Ddtrace=enabled
           CC: ccache clang
           CXX: ccache clang++
+          CLANG: ccache clang
         run: *compiler_warnings_cmd
 
       - name: mingw warnings (cross compilation)
         if: ${{ !cancelled() }}
         env:
-          CONF: --host=x86_64-w64-mingw32ucrt --enable-cassert --without-icu
-          CC: ccache x86_64-w64-mingw32ucrt-gcc
-          CXX: ccache x86_64-w64-mingw32ucrt-g++
+          CONF: >-
+            --cross-file src/tools/ci/meson-cross-w64-ucrt.txt
+            --buildtype debug
+            -Db_pch=true
+            -Dcassert=true
         run: *compiler_warnings_cmd
 
       ###
@@ -1241,12 +1246,8 @@ jobs:
       # XXX: Only do this if there have been changes in doc/ since last build
       - name: Build documentation
         if: ${{ !cancelled() }}
-        env:
-          CONF: --cache gcc.cache
-          CC: ccache gcc
-          CXX: ccache g++
-          DEFAULT_BUILD: -C doc
-        run: *compiler_warnings_cmd
+        run:
+          ninja -C build-meson docs
 
       ###
       # Verify headerscheck / cpluspluscheck succeed
@@ -1261,7 +1262,6 @@ jobs:
           echo "::group::configure"
           ./configure \
             ${{env.LINUX_CONFIGURE_FEATURES}} \
-            --cache gcc.cache \
             --quiet \
             CC="ccache gcc" CXX="ccache g++" CLANG="ccache clang"
           echo "::endgroup::"
diff --git a/src/tools/ci/meson-cross-w64-ucrt.txt b/src/tools/ci/meson-cross-w64-ucrt.txt
new file mode 100644
index 00000000000..b6144979416
--- /dev/null
+++ b/src/tools/ci/meson-cross-w64-ucrt.txt
@@ -0,0 +1,21 @@
+[constants]
+triple = 'x86_64-w64-mingw32ucrt'
+prefix = '/usr/bin' / triple + '-'
+
+[binaries]
+c = ['ccache', prefix + 'gcc']
+cpp = ['ccache', prefix + 'g++']
+ar = prefix + 'ar'
+strip = prefix + 'strip'
+pkg-config = prefix + 'pkg-config'
+windres = prefix + 'windres'
+
+[properties]
+# Directory that contains 'bin', 'lib', etc
+root = '/usr/x86_64-w64-mingw32ucrt'
+
+[host_machine]
+system = 'windows'
+cpu_family = 'x86_64'
+cpu = 'x86_64'
+endian = 'little'
-- 
2.54.0.450.g9ac3f193c0