build: work around repetitive pacman failures by retrying.

MSYS2 pacman gets randomly stuck on Windows/Aarch64. The actual issue is still
being investigated by upstream projects, though anyway it's bad for us right
now, to the point that there are discussions to remove Aarch64 support from the
Windows installer (whereas it just got added recently!) in #10729.

This is an attempt to a workaround. Instead of getting stuck forever and waiting
until the whole job times out (per Gitlab CI settings), I time-out the pacman
command within our script and try again, up to 2 more times. Hopefully one of
the calls would succeed.

See: msys2/MSYS2-packages#4340

build/windows/gitlab-ci/1_build-deps-msys2.sh

@@ -35,10 +35,21 @@ fi
 export DEPS_PATH="build/windows/gitlab-ci/all-deps-uni.txt"
 sed -i "s/DEPS_ARCH_/${MINGW_PACKAGE_PREFIX}-/g" $DEPS_PATH
 export GIMP_DEPS=`cat $DEPS_PATH`
-pacman --noconfirm -S --needed git                                \
-                               base-devel                         \
-                               ${MINGW_PACKAGE_PREFIX}-toolchain  \
-                               $GIMP_DEPS
+
+retry=3
+while [ $retry -gt 0 ]; do
+  : $((--retry))
+  timeout 10m pacman --noconfirm -S --needed git                                \
+                                             base-devel                         \
+                                             ${MINGW_PACKAGE_PREFIX}-toolchain  \
+                                             $GIMP_DEPS && break
+  echo "MSYS2 pacman timed out. Trying again."
+done
+
+if [ $? -ne 0 ]; then
+  echo "MSYS2 pacman repeatedly failed. See: https://github.com/msys2/MSYS2-packages/issues/4340"
+  exit 1
+fi
 
 
 # Clone babl and GEGL (follow master branch)

build/windows/gitlab-ci/2_build-gimp-msys2.sh

@@ -43,9 +43,20 @@ fi
 export DEPS_PATH="build/windows/gitlab-ci/all-deps-uni.txt"
 sed -i "s/DEPS_ARCH_/${MINGW_PACKAGE_PREFIX}-/g" $DEPS_PATH
 export GIMP_DEPS=`cat $DEPS_PATH`
-pacman --noconfirm -S --needed base-devel                         \
-                               ${MINGW_PACKAGE_PREFIX}-toolchain  \
-                               $GIMP_DEPS
+
+retry=3
+while [ $retry -gt 0 ]; do
+  : $((--retry))
+  timeout 10m pacman --noconfirm -S --needed base-devel                         \
+                                             ${MINGW_PACKAGE_PREFIX}-toolchain  \
+                                             $GIMP_DEPS && break
+  echo "MSYS2 pacman timed out. Trying again."
+done
+
+if [ $? -ne 0 ]; then
+  echo "MSYS2 pacman repeatedly failed. See: https://github.com/msys2/MSYS2-packages/issues/4340"
+  exit 1
+fi
 
 # Install QOI header manually
 # mingw32 package of qoi was removed from MSYS2, we have download it by ourselves
@@ -145,4 +156,4 @@ if [[ "$BUILD_TYPE" == "CI_NATIVE" ]]; then
   mv "${GIMP_PREFIX}" .
 else
   make_cmd local $MSYS2_PREFIX
-fi
+fi

build/windows/gitlab-ci/3_package-gimp-uni_base.sh

@@ -24,13 +24,23 @@ fi
 
 
 if [[ "$BUILD_TYPE" != "CI_CROSS" ]]; then
-# Install the required (pre-built) packages again
-export DEPS_PATH="build/windows/gitlab-ci/all-deps-uni.txt"
-sed -i "s/DEPS_ARCH_/${MINGW_PACKAGE_PREFIX}-/g" $DEPS_PATH
-export GIMP_DEPS=`cat $DEPS_PATH`
-pacman --noconfirm -S --needed base-devel                         \
-                               ${MINGW_PACKAGE_PREFIX}-toolchain  \
-                               $GIMP_DEPS
+  # Install the required (pre-built) packages again
+  export DEPS_PATH="build/windows/gitlab-ci/all-deps-uni.txt"
+  sed -i "s/DEPS_ARCH_/${MINGW_PACKAGE_PREFIX}-/g" $DEPS_PATH
+  export GIMP_DEPS=`cat $DEPS_PATH`
+  retry=3
+  while [ $retry -gt 0 ]; do
+    : $((--retry))
+    timeout 10m pacman --noconfirm -S --needed base-devel                         \
+                                               ${MINGW_PACKAGE_PREFIX}-toolchain  \
+                                               $GIMP_DEPS && break
+    echo "MSYS2 pacman timed out. Trying again."
+  done
+
+  if [ $? -ne 0 ]; then
+    echo "MSYS2 pacman repeatedly failed. See: https://github.com/msys2/MSYS2-packages/issues/4340"
+    exit 1
+  fi
 fi
 
 
@@ -177,4 +187,4 @@ done
 libList=$(find ${GIMP_DISTRIB}/lib/ \( -iname '*.dll' -or -iname '*.exe' \)) && libArray=($libList)
 for lib in "${libArray[@]}"; do
   python3 build/windows/gitlab-ci/3_package-gimp-uni_dep.py $lib ${GIMP_PREFIX}/ ${MSYS_PREFIX}/ ${GIMP_DISTRIB} --output-dll-list done-dll.list;
-done
+done