ci: enable C-style operators and GTK3 for the IDE build

The IDE is upstream objfpc code that uses `+=`; the lazbuild build path
(unlike the Makefile's -Sci) needs C-operators enabled, so add -Sci to the
generated fpc.cfg on both runners. Upstream also defaults the Linux widgetset
to gtk3, so swap libgtk2.0-dev for libgtk-3-dev on the Linux runner.

Author: fibodevy

.github/workflows/linux.yml

@@ -19,7 +19,7 @@ jobs:
         sudo apt-get update -o Acquire::Retries=3
         sudo apt-get install -y --no-install-recommends \
           make zip rsync curl \
-          libgtk2.0-dev libcairo2-dev libpango1.0-dev \
+          libgtk-3-dev libcairo2-dev libpango1.0-dev \
           libgdk-pixbuf2.0-dev libatk1.0-dev libgl1-mesa-dev
 
     - name: Download FPC Unleashed nightly
@@ -33,6 +33,9 @@ jobs:
         target=x86_64-linux
         {
           echo "# FPC Unleashed minimal config"
+          # the IDE is upstream objfpc code that uses C-style operators (+=); the
+          # Makefile build passes -Sci but the lazbuild IDE build does not
+          echo "-Sci"
           for d in "$HOME/fpc/units/$target"/*/; do
             [ -d "$d" ] || continue
             echo "-Fu${d%/}"

.github/workflows/windows.yml

@@ -27,7 +27,9 @@ jobs:
       run: |
         $target = "x86_64-win64"
         $cfg = "C:\fpc\bin\$target\fpc.cfg"
-        $lines = @("# FPC Unleashed minimal config")
+        # the IDE is upstream objfpc code that uses C-style operators (+=); the
+        # Makefile build passes -Sci but the lazbuild IDE build does not
+        $lines = @("# FPC Unleashed minimal config", "-Sci")
         foreach ($d in Get-ChildItem -Path "C:\fpc\units\$target" -Directory) {
           $lines += "-Fu$($d.FullName)"
         }