ElementsProject · rustyrussell · Apr 30, 2026 · Apr 30, 2026 · Apr 30, 2026 · Apr 30, 2026
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
@@ -312,6 +312,42 @@ jobs:
         run: |
           uv run eatmydata make -j $(nproc) check-units installcheck VALGRIND=${{ matrix.VALGRIND }} CARGO=false CC=devtools/cc-nobuild SUPPRESS_GENERATION=1
 
+  compile-32bit:
+    name: Build 32-bit (size_t != 64-bit warnings)
+    runs-on: ubuntu-24.04
+    timeout-minutes: 30
+    needs:
+      - prebuild
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Add i386 architecture
+        run: |
+          sudo dpkg --add-architecture i386
+          sudo apt-get update -qq
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Install dependencies
+        env:
+          TEST_NETWORK: ${{ matrix.TEST_NETWORK }}
+        run: |
+          bash -x .github/scripts/setup.sh
+          sudo apt-get install --no-install-recommends -yy \
+            gcc-multilib \
+            libsodium-dev:i386 \
+            libsqlite3-dev:i386 \
+            zlib1g-dev:i386
+
+      - name: Build
+        env:
+          PKG_CONFIG_PATH: /usr/lib/i386-linux-gnu/pkgconfig
+        run: |
+          ./configure --disable-rust --enable-debugbuild CC="gcc -m32" 
+          uv run make -j $(nproc) all-programs
+
   check-fuzz:
     name: Run fuzz regression tests
     runs-on: ubuntu-24.04
@@ -905,11 +941,12 @@ jobs:
       - min-btc-support
       - check-downgrade
       - check-compiled-source
+      - compile-32bit
     if: ${{ always() }}
     steps:
       - name: Complete
         env:
-          JOB_NAMES: "FIRST_INTEGRATION FULL_INTEGRATION CHECK_UNITS VALGRIND SANITIZERS BTC CHECK_COMPILED_SOURCE"
+          JOB_NAMES: "FIRST_INTEGRATION FULL_INTEGRATION CHECK_UNITS VALGRIND SANITIZERS BTC CHECK_COMPILED_SOURCE COMPILE_32BIT"
           FIRST_INTEGRATION: ${{ needs['first-integration'].result }}
           FULL_INTEGRATION: ${{ needs['full-integration'].result }}
           CHECK_UNITS: ${{ needs['check-units'].result }}
@@ -919,6 +956,7 @@ jobs:
           BTC: ${{ needs['min-btc-support'].result }}
           CHECK_DOWNGRADE: ${{ needs['check-downgrade'].result }}
           CHECK_COMPILED_SOURCE: ${{ needs['check-compiled-source'].result }}
+          COMPILE_32BIT: ${{ needs['compile-32bit'].result }}
         run: |
           failed=""
           for name in $JOB_NAMES; do

diff --git a/configure b/configure
@@ -6,7 +6,7 @@ set -e
 CONFIGURATOR=ccan/tools/configurator/configurator
 CONFIG_VAR_FILE=config.vars
 CONFIG_HEADER=ccan/config.h
-BASE_WARNFLAGS="-Wall -Wundef -Wmissing-prototypes -Wmissing-declarations -Wstrict-prototypes -Wold-style-definition -Werror"
+BASE_WARNFLAGS="-Wall -Wundef -Wmissing-prototypes -Wmissing-declarations -Wstrict-prototypes -Wold-style-definition"
 
 OS=$(uname -s)
 ARCH=$(uname -m)
@@ -51,7 +51,7 @@ default_coptflags()
     fi
 }
 
-# Given COPTFLAGS, HAVE_GCC and HAVE_MODERN_GCC, what CWARNFLAGS to default to?
+# Given COPTFLAGS, HAVE_GCC, HAVE_MODERN_GCC and DEBUGBUILD, what CWARNFLAGS to default to?
 default_cwarnflags()
 {
     F=$BASE_WARNFLAGS
@@ -66,6 +66,10 @@ default_cwarnflags()
 	# this gcc-only.
 	F="$F -Wshadow=local"
     fi
+    # Debug builds get -Werror (great for CI!)
+    if [ "$4" = 1 ]; then
+	F="$F -Werror"
+    fi
     echo "$F"
 }
 
@@ -74,7 +78,7 @@ default_python()
     PYTHON_BINS="python3 python"
     for p in $PYTHON_BINS; do
         if [ "$(which $p)" != "" ] ; then
-            if $p --version 2>&1 | grep -q "Python 3."; then
+            if uv run $p --version 2>&1 | grep -q "Python 3."; then
                 echo "$p"
                 return
             fi
@@ -112,14 +116,14 @@ default_pytest()
 	# want to only call which on the executable
 	exe=$(echo "$p" | awk '{print $1}')
 	# shellcheck disable=SC2086
-	if [ "$(which $exe)" != "" ] ; then
-	    "$p" --version 2>&1 | grep -q "pytest" || continue
+	if [ "$(uv run which $exe)" != "" ] ; then
+	    uv run "$p" --version 2>&1 | grep -q "pytest" || continue
 	    echo "$p"
 	    return
 	fi
     done
 
-    if $1 -c "import pytest" 2>/dev/null; then
+    if uv run $1 -c "import pytest" 2>/dev/null; then
         echo "$1 -m pytest"
         return
     fi
@@ -220,7 +224,8 @@ have_function_sections()
     TMPOBJFILE=$CONFIG_VAR_FILE.$$.o
 
     echo "int foo(void); int foo(void) { return 0; }" > $TMPCFILE
-    $1 $2 -ffunction-sections -Wl,--gc-sections -c $TMPCFILE -o $TMPOBJFILE
+    # We *want* this to fail if we get a warning, hence use -Werror.
+    $1 $2 -Werror -ffunction-sections -Wl,--gc-sections -c $TMPCFILE -o $TMPOBJFILE
 }
 
 usage()
@@ -231,7 +236,7 @@ usage()
     set_defaults
     DEFAULT_COPTFLAGS="$(default_coptflags $DEBUGBUILD)"
     # We assume we have a modern gcc.
-    DEFAULT_CWARNFLAGS="$(default_cwarnflags ""$DEFAULT_COPTFLAGS"" 1 1)"
+    DEFAULT_CWARNFLAGS="$(default_cwarnflags ""$DEFAULT_COPTFLAGS"" 1 1 ""$DEBUGBUILD"")"
     usage_with_default "CC" "$CC"
     usage_with_default "CWARNFLAGS" "$DEFAULT_CWARNFLAGS"
     usage_with_default "COPTFLAGS" "$DEFAULT_COPTFLAGS"
@@ -531,12 +536,6 @@ code=
 /*END*/
 EOF
 
-if check_command 'python3-mako' python3 -c 'import mako'; then
-    HAVE_PYTHON3_MAKO=1
-else
-    HAVE_PYTHON3_MAKO=0
-fi
-
 if ! check_command 'lowdown' lowdown; then
     echo "*** We need lowdown!" >&2
     exit 1
@@ -601,7 +600,8 @@ fi
 if [ -z ${CWARNFLAGS+x} ]; then
     CWARNFLAGS=$(default_cwarnflags "$COPTFLAGS" \
 		    $(sed -n 's/^HAVE_GCC=//p' < $CONFIG_VAR_FILE.$$) \
-		    $(sed -n 's/^HAVE_MODERN_GCC=//p' < $CONFIG_VAR_FILE.$$) )
+		    $(sed -n 's/^HAVE_MODERN_GCC=//p' < $CONFIG_VAR_FILE.$$) \
+		    "$DEBUGBUILD")
 fi
 
 add_var PREFIX "$PREFIX"
@@ -632,7 +632,6 @@ add_var CLANG_COVERAGE "$CLANG_COVERAGE"
 add_var ASAN "$ASAN"
 add_var UBSAN "$UBSAN"
 add_var TEST_NETWORK "$TEST_NETWORK"
-add_var HAVE_PYTHON3_MAKO "$HAVE_PYTHON3_MAKO"
 add_var SHA256SUM "$SHA256SUM"
 add_var FUZZING "$FUZZING"
 add_var RUST "$RUST"

diff --git a/tools/test/Makefile b/tools/test/Makefile
@@ -6,8 +6,6 @@
 # We generate the files, and then we attempt to compile
 # and run a test case.
 
-# We don't run these at all unless mako is installed.
-ifeq ($(HAVE_PYTHON3_MAKO),1)
 check-units: check-tools
 
 TOOL_TEST_INCL_SRC := tools/test/enum.c
@@ -44,7 +42,6 @@ tools/test/print_gen.c: $(TOOLS_WIRE_DEPS)
 ALL_TEST_PROGRAMS += $(TOOL_TEST_PROGRAMS)
 
 check-tools: $(TOOL_TEST_PROGRAMS:%=unittest/%)
-endif # HAVE_PYTHON3_MAKO
 
 clean: tools-test-clean