CI: Build libbacktrace in Linux deps

.github/workflows/scripts/linux/build-dependencies-qt.sh

@@ -6,12 +6,14 @@ INSTALLDIR="$HOME/deps"
 NPROCS="$(getconf _NPROCESSORS_ONLN)"
 SDL=SDL2-2.26.0
 QT=6.3.1
+LIBBACKTRACE=ad106d5fdd5d960bd33fae1c48a351af567fd075
 
 mkdir -p deps-build
 cd deps-build
 
 cat > SHASUMS <<EOF
 8000d7169febce93c84b6bdf376631f8179132fd69f7015d4dadb8b9c2bdb295  $SDL.tar.gz
+fd6f417fe9e3a071cf1424a5152d926a34c4a3c5070745470be6cf12a404ed79  $LIBBACKTRACE.zip
 0a64421d9c2469c2c48490a032ab91d547017c9cc171f3f8070bc31888f24e03  qtbase-everywhere-src-$QT.tar.xz
 7b19f418e6f7b8e23344082dd04440aacf5da23c5a73980ba22ae4eba4f87df7  qtsvg-everywhere-src-$QT.tar.xz
 c412750f2aa3beb93fce5f30517c607f55daaeb7d0407af206a8adf917e126c1  qttools-everywhere-src-$QT.tar.xz
@@ -21,6 +23,7 @@ EOF
 
 curl -L \
 	-O "https://libsdl.org/release/$SDL.tar.gz" \
+	-O "https://github.com/ianlancetaylor/libbacktrace/archive/$LIBBACKTRACE.zip" \
 	-O "https://download.qt.io/official_releases/qt/${QT%.*}/$QT/submodules/qtbase-everywhere-src-$QT.tar.xz" \
 	-O "https://download.qt.io/official_releases/qt/${QT%.*}/$QT/submodules/qtsvg-everywhere-src-$QT.tar.xz" \
 	-O "https://download.qt.io/official_releases/qt/${QT%.*}/$QT/submodules/qttools-everywhere-src-$QT.tar.xz" \
@@ -37,6 +40,14 @@ make "-j$NPROCS"
 make install
 cd ..
 
+echo "Building libbacktrace..."
+unzip "$LIBBACKTRACE.zip"
+cd "libbacktrace-$LIBBACKTRACE"
+./configure --prefix="$HOME/deps"
+make
+make install
+cd ..
+
 # Couple notes:
 # -fontconfig is needed otherwise Qt Widgets render only boxes.
 # -qt-doubleconversion avoids a dependency on libdouble-conversion.