Turn on DTD checking and differentiate error messages.

While there was a definition for the pre-bigvm case, with 24-bit
pointers, for byteswapped (little-endian) systems, there was no
structure definition for the bigvm case, with 28-bit pointers.

.github/workflows/Dockerfile_builder

@@ -0,0 +1,18 @@
+#*******************************************************************************
+#
+#  Dockerfile to build image with all the tools to build  Maiko
+#
+#  Copyright 2023 by Interlisp.org
+#
+#  Frank Halasz 2023-02-21
+#
+# ******************************************************************************
+
+FROM ubuntu:latest
+SHELL ["/bin/bash", "-c"]
+USER root:root
+# Install build tools
+RUN apt-get update && apt-get install -y make clang libx11-dev gcc
+USER root
+WORKDIR /root
+ENTRYPOINT /bin/bash

.github/workflows/Dockerfile_maiko

@@ -0,0 +1,25 @@
+#*******************************************************************************
+#
+#  Dockerfile to build Maiko for Linux to be used by buildRelease github action
+#  The output of this is intended to be a directory in the github workspace
+#  file system it is not intended to be a useable Docker image.
+#
+#  Copyright 2023 by Interlisp.org
+#
+#  Frank Halasz 2023-02-21
+#
+# ******************************************************************************
+
+FROM ghcr.io/interlisp/maiko-builder
+ARG INSTALL_LOCATION=/usr/local/interlisp/maiko
+SHELL ["/bin/bash", "-c"]
+# Copy over / clean maiko repo
+COPY . ${INSTALL_LOCATION}
+# Build maiko
+RUN cd ${INSTALL_LOCATION}/bin \
+    && ./makeright x cleanup \
+    && ./makeright x
+RUN cd ${INSTALL_LOCATION}/bin \
+    && if [ "$(./machinetype)" = "x86_64" ]; then \
+           ./makeright init; \
+       fi

.github/workflows/buildBuilderImage.yml

@@ -32,15 +32,9 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      # Checkout just the relevant Dockerfile
-      - name: Checkout files
-        uses: Bhacaz/checkout-files@v2
-        with:
-          files: .github/workflows/Dockerfile_builder
-
-      # Checkout the branch of maiko code  
-      #- name: Checkout
-      #  uses: actions/checkout@v3
+      # Checkout maiko
+      - name: Checkout maiko
+        uses: actions/checkout@v3
 
       # Setup docker environment variables
       - name: Setup Docker Environment Variables
@@ -49,7 +43,7 @@ jobs:
           DOCKER_REGISTRY="ghcr.io"
           DOCKER_NAMESPACE=$(echo "${{ github.repository_owner }}" | tr '[:upper:]' '[:lower:]')
           DOCKER_REPO=${DOCKER_REGISTRY}/${DOCKER_NAMESPACE}/maiko-builder
-          DOCKER_TAGS="${DOCKER_REPO}:latest
+          DOCKER_TAGS="${DOCKER_REPO}:latest"
           echo "BUILD_DATE=$(date -u +'%Y-%m-%dT%H:%M:%SZ')" >> ${GITHUB_ENV}
           echo "DOCKER_TAGS=${DOCKER_TAGS}" >> ${GITHUB_ENV}
 
@@ -66,7 +60,7 @@ jobs:
 
       # Login to ghcr.io
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v2 
+        uses: docker/login-action@v2
         with:
           registry: ghcr.io
           username: ${{ github.repository_owner }}
@@ -89,5 +83,5 @@ jobs:
           push: true
           tags: ${{ env.DOCKER_TAGS }}
 
-          
+
 ######################################################################################

.github/workflows/buildRelease.yml

@@ -1,30 +1,27 @@
 #*******************************************************************************
-# buidReleaseInclDocker.yml
+# buidRelease.yml
 #
-# Workflow to build a Maiko release that is pushed to github as well as
-# Docker images incorporating the release, which are pushed to Docker Hub.
-# For linux:  release assets are built/pushed for X86_64, aarch64 and arm7vl and 
-#     a multiplatform Docker image is pushed.
-# For macOS:  release assets are built/pushed for X86_64. (No aarch64 as yet.)
+# Workflow to build a Maiko release that is pushed to github.
+# For linux:  release assets are built/pushed for X86_64, aarch64 and arm7vl.
+# For macOS:  release assets are built/pushed for X86_64 and aarch64 as well as
+#             a set of universal binaries.
 # For Windows:  not supported
 #
 # Note release pushed to github automatically includes source code assets
 # in tar and zip formats.
 #
 # 2022-01-16 by Frank Halasz based on earlier workflow called buildDocker.yml
+# Updated 2023-06-06: Remove docker image push; increase build efficeincy for linux
 #
-# Copyright 2022 by Interlisp.org
+# Copyright 2022-2023 by Interlisp.org
 #
 #
 # ******************************************************************************
 
-name: 'Build/Push Release & Docker Image'
-
-env:
-  workflow: 'buildReleaseInclDocker.yml'
+name: 'Build/Push Release'
 
 # Run this workflow on ...
-on: 
+on:
     workflow_dispatch:
       inputs:
         draft:
@@ -66,14 +63,18 @@ defaults:
   run:
     shell: bash
 
-#  2 separate jobs here that can run in parallel
+#  3 separate jobs here that can run in parallel
 #
-#  1.  Linux: Build/push a multiplatform Linux Docker image and use results to
-#      build/push Linux release assets.
+#  1.  Linux: Build a multiplatform Linux Docker file system (not saved) and use
+#      results to build/push Linux release assets.
 #
-#  2.  MacOs:  Build maiko for MacOS (x86_64, aarch64, and universal)  then create
+#  2.  MacOs:  Build maiko for MacOS (x86_64, aarch64, and universal) then create
 #      and push release assets.
 #
+#  3. Windows: Build maiko for cygwin and SDL (x86_64).  Build is done within the
+#     cygwin-maiko-builder Docker image by building a new docker files system (and
+#     not a docker container) which is used to build/push Windows(cygwin) assets.
+#
 
 jobs:
 
@@ -87,6 +88,9 @@ jobs:
     outputs:
       draft: ${{ steps.one.outputs.draft }}
       force: ${{ steps.one.outputs.force }}
+      linux: ${{ steps.one.outputs.linux }}
+      macos: ${{ steps.one.outputs.macos }}
+      windows: ${{ steps.one.outputs.windows }}
     steps:
       - id: one
         run: >
@@ -99,9 +103,11 @@ jobs:
               echo "workflow_call";
               echo "draft=${{ inputs.draft }}" >> $GITHUB_OUTPUT;
               echo "force=${{ inputs.force }}" >> $GITHUB_OUTPUT;
-          fi
-        
-
+          fi;
+          echo "linux=true" >> $GITHUB_OUTPUT;
+          echo "macos=true" >> $GITHUB_OUTPUT;
+          echo "windows=true" >> $GITHUB_OUTPUT;
+          
 
 ######################################################################################
 
@@ -114,7 +120,7 @@ jobs:
     outputs:
       release_not_built: ${{ steps.check.outputs.release_not_built }}
 
-    steps: 
+    steps:
       # Checkout the actions for this repo owner
       - name: Checkout Actions
         uses: actions/checkout@v3
@@ -124,7 +130,7 @@ jobs:
       - run: mv ./Actions_${{ github.sha }}/actions ../actions && rm -rf ./Actions_${{ github.sha }}
 
       # Check if build already run for this commit
-      - name: Build already completed? 
+      - name: Build already completed?
         id: check
         continue-on-error: true
         uses: ./../actions/check-sentry-action
@@ -137,12 +143,15 @@ jobs:
   # Use docker images to create and push release assets to github
 
   linux:
-  
+
     needs: [inputs, sentry]
     if: |
-      needs.sentry.outputs.release_not_built == 'true'
-      || needs.inputs.outputs.force == 'true'
-    
+      needs.inputs.outputs.linux == 'true'
+      && (
+         needs.sentry.outputs.release_not_built == 'true'
+         || needs.inputs.outputs.force == 'true'
+      )
+
     runs-on: ubuntu-latest
 
     steps:
@@ -154,7 +163,7 @@ jobs:
           path: ./Actions_${{ github.sha }}
       - run: mv ./Actions_${{ github.sha }}/actions ../actions && rm -rf ./Actions_${{ github.sha }}
 
-      # Checkout the branch  
+      # Checkout the branch
       - name: Checkout
         uses: actions/checkout@v3
 
@@ -174,33 +183,27 @@ jobs:
           echo "build_time=$(date -u +'%Y-%m-%dT%H:%M:%SZ')" >> $GITHUB_OUTPUT
           echo "docker_tags=${DOCKER_TAGS}"  >> $GITHUB_OUTPUT
 
-      # Setup the Docker Machine Emulation environment.  
+      # Setup the Docker Machine Emulation environment.
       - name: Set up QEMU
-        uses: docker/setup-qemu-action@master
+        uses: docker/setup-qemu-action@v2
         with:
           platforms: linux/amd64,linux/arm64,linux/arm/v7
 
       # Setup the Docker Buildx funtion
       - name: Set up Docker Buildx
         id: buildx
-        uses: docker/setup-buildx-action@master
-
-      # Login into DockerHub - required to store the created image
-      - name: Login to DockerHub
-        uses: docker/login-action@v2
-        with:
-          username: ${{ secrets.DOCKER_USERNAME }}
-          password: ${{ secrets.DOCKER_PASSWORD }}
+        uses: docker/setup-buildx-action@v2
 
       # Do the Docker Build using the Dockerfile in the repository we
-      # checked out.  Push the result to Docker Hub.
+      # checked out.  Save the results in a directory under /tmp to be used
+      # for creating release tars.  Does not creatre a docker image and does not
+      # push anything to Docker Hub.
       #
       # NOTE: THE ACTUAL MAIKO BUILD (FOR LINUX) HAPPENS HERE - I.E., IN THE
       #       DOCKER BUILD CALL.  BUILD COMMANDS ARE SPECIFIED IN THE
       #       Dockerfile, NOT HERE IN THE WORKFLOW.
       #
-      - name: Build Docker Image for Push to Docker Hub
-        if: ${{ true }}
+      - name: Build Docker Image and Save It Locally
         uses: docker/build-push-action@v4
         with:
           builder: ${{ steps.buildx.outputs.name }}
@@ -208,23 +211,7 @@ jobs:
             BUILD_DATE=${{ steps.docker_env.outputs.build_time }}
             RELEASE_TAG=${{ steps.tag.outputs.release_tag }}
           context: .
-          file: ./Dockerfile
-          platforms: linux/amd64,linux/arm64,linux/arm/v7
-          # Push the result to DockerHub
-          push: true
-          tags: ${{ steps.docker_env.outputs.docker_tags }}
-
-      # Redo the Docker Build (hopefully mostly using the cache from the previous build).
-      # But save the results in a directory under /tmp to be used for creating release tars.
-      - name: Rebuild Docker Image For Saving Locally
-        uses: docker/build-push-action@v4
-        with:
-          builder: ${{ steps.buildx.outputs.name }}
-          build-args: |
-            BUILD_DATE=${{ steps.docker_env.outputs.build_time }}
-            RELEASE_TAG=${{ steps.tag.outputs.release_tag }}
-          context: .
-          file: ./Dockerfile
+          file: ./.github/workflows/Dockerfile_maiko
           platforms: linux/amd64,linux/arm64,linux/arm/v7
           # Put the results out to the local file system
           outputs: type=local,dest=/tmp/docker_images
@@ -254,7 +241,7 @@ jobs:
       # Push Release to github
       - name: Push the release
         uses: ncipollo/release-action@v1
-        with: 
+        with:
           allowUpdates: true
           artifacts:
             /tmp/release_tars/${{ steps.tag.outputs.release_tag }}-linux.x86_64.tgz,
@@ -273,14 +260,17 @@ jobs:
 
     needs: [inputs, sentry]
     if: |
-      needs.sentry.outputs.release_not_built == 'true'
-      || needs.inputs.outputs.force == 'true'
+      needs.inputs.outputs.macos == 'true'
+      && (
+          needs.sentry.outputs.release_not_built == 'true'
+          || needs.inputs.outputs.force == 'true'
+      )
 
     runs-on: macos-latest
 
     steps:
 
-      # Checkout the branch  
+      # Checkout the branch
       - name: Checkout
         uses: actions/checkout@v3
 
@@ -325,7 +315,7 @@ jobs:
           sudo ditto /Volumes/SDL2/SDL2.framework /Library/Frameworks/SDL2.framework
           hdiutil detach /Volumes/SDL2/
 
-      # Build maiko   
+      # Build maiko
       - name: Build ldeinit
         working-directory: ./bin
         run: |
@@ -389,6 +379,98 @@ jobs:
           draft: ${{ needs.inputs.outputs.draft }}
           token: ${{ secrets.GITHUB_TOKEN }}
 
+######################################################################################
+
+  # Windows: build for Windows-Cygwin via Docker build and use results to
+  # create and push release assets to github
+  
+  windows:
+
+    needs: [inputs, sentry]
+    if: |
+      needs.inputs.outputs.windows == 'true'
+      && (
+          needs.sentry.outputs.release_not_built == 'true'
+          || needs.inputs.outputs.force == 'true'
+      )
+
+    runs-on: windows-2022
+
+    defaults:
+      run:
+        shell: powershell
+
+    steps:
+
+      # setup git to not mess up line endings
+      - name: git config
+        run: git config --global core.autocrlf input
+
+      # Retrieve Cygwin setup and install cygwin
+      - name: Install cygwin
+        id: cygwin
+        run: |
+          wget https://cygwin.com/setup-x86_64.exe -OutFile setup-x86_64.exe
+          Unblock-File setup-x86_64.exe
+          Start-Process setup-x86_64.exe -Wait -ArgumentList @("--root", ".\cygwin", "--quiet-mode", "--no-admin", "--wait", "--no-shortcuts", "--no-write-registry",  "--verbose", "--site", "http://www.gtlib.gatech.edu/pub/cygwin/", "--packages", "nano,binutils,make,cmake,gcc,clang")
+          cygwin\bin\bash -login -c 'sed -i -e "s/^none/#none/" /etc/fstab; echo "none / cygdrive binary,posix=0,user 0 0" >>/etc/fstab'
+
+      # Retrieve SDL2 and install in cygwin
+      - name: Install SDL2
+        id: sdl2
+        env: 
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          gh release download 2.26.5 --repo interlisp/cygwin-sdl --pattern *.tgz --output .\cygwin\sdl2.tar.gz
+          cygwin\bin\bash -login -c 'cd /; tar xzf sdl2.tar.gz'
+
+      # Checkout the branch
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          path: cygwin\maiko
+
+      # Checkout the actions for this repo owner
+      - name: Checkout Actions
+        uses: actions/checkout@v3
+        with:
+          repository: ${{ github.repository_owner }}/.github
+          path: ./Actions_${{ github.sha }}
+      - run: |
+          mv ./Actions_${{ github.sha }}/actions ../actions
+          rm -recurse -force ./Actions_${{ github.sha }}
+
+      # Setup release tag
+      - name: Setup Release Tag
+        id: tag
+        uses: ./../actions/release-tag-action
+        with:
+          path: cygwin/maiko
+
+      # Build maiko TODO-cleanup
+      - name: Build Cygwin-SDL Maiko
+        run: |
+          cygwin\bin\bash -login -c 'cd /maiko/bin && ./makeright sdl cleanup && ./makeright sdl'
+          cygwin\bin\bash -login -c 'mkdir /tmp/maiko; mkdir /tmp/maiko/bin; mkdir /tmp/maiko/cygwin.x86_64'
+          cygwin\bin\bash -login -c 'cp /maiko/bin/osversion /tmp/maiko/bin; cp /maiko/bin/machinetype /tmp/maiko/bin'
+          cygwin\bin\bash -login -c 'cp /maiko/bin/config.guess /tmp/maiko/bin; cp /maiko/bin/config.sub /tmp/maiko/bin'
+          cygwin\bin\bash -login -c 'cp /maiko/cygwin.x86_64/* /tmp/maiko/cygwin.x86_64; cp /usr/local/bin/SDL2.DLL /tmp/maiko/cygwin.x86_64'
+          cygwin\bin\bash -login -c 'chmod +x /tmp/maiko/bin/*; chmod +x /tmp/maiko/cygwin.x86_64/*'
+          cygwin\bin\bash -login -c 'echo lde > /tmp/maiko/cygwin.x86_64/lde.exe.local; echo ldesdl > /tmp/maiko/cygwin.x86_64/ldesdl.exe.local'
+          cygwin\bin\bash -login -c 'mkdir -p /tmp/release_tars'
+          cygwin\bin\bash -login -c 'tar -c -z -C /tmp -f /tmp/release_tars/${{ steps.tag.outputs.release_tag }}-cygwin.x86_64.tgz maiko'
+
+     # Push Release to github
+      - name: Push the release
+        uses: ncipollo/release-action@v1
+        with:
+          allowUpdates: true
+          artifacts:
+            cygwin/tmp/release_tars/${{ steps.tag.outputs.release_tag }}-cygwin.x86_64.tgz
+          tag: ${{ steps.tag.outputs.release_tag }}
+          draft: ${{ needs.inputs.outputs.draft }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+
 
 
 ######################################################################################
@@ -403,9 +485,9 @@ jobs:
     outputs:
       build_successful: ${{ steps.output.outputs.build_successful }}
 
-    needs: [inputs, sentry, linux, macos]
+    needs: [inputs, sentry, linux, macos, windows]
 
-    steps: 
+    steps:
       # Checkout the actions for this repo owner
       - name: Checkout Actions
         uses: actions/checkout@v3
@@ -415,16 +497,15 @@ jobs:
       - run: mv ./Actions_${{ github.sha }}/actions ../actions && rm -rf ./Actions_${{ github.sha }}
 
       # Set sentry
-      - name: Is build for this commit already completed? 
+      - name: Is build for this commit already completed?
         id: set
         uses: ./../actions/set-sentry-action
         with:
           tag: "release_docker"
-     
+
       - name: Output
         id: output
         run: |
           echo "build_successful=true"  >> $GITHUB_OUTPUT
 
-          
 ######################################################################################

.gitignore

@@ -22,9 +22,12 @@ cmake-build-*/**
 *.armv7l-x/**
 *.armv7l/**
 *.aarch64-x/**
+*.aarch64-sdl/**
 *.aarch64/**
 init.386/**
 *.universal/**
 # core files
 core
 *.core
+*.swp
+

Dockerfile

@@ -1,55 +0,0 @@
-#*******************************************************************************
-#
-#  Dockerfile to build Maiko (Stage 1) and create a Docker image and push it
-#  to DockerHub (stage 2).
-#
-#  Copyright 2022 by Interlisp.org
-#
-# ******************************************************************************
-
-#
-#  Build Maiko Stage
-#
-FROM ubuntu:focal AS builder
-SHELL ["/bin/bash", "-c"]
-USER root:root
-# Install build tools
-RUN apt-get update && apt-get install -y make clang libx11-dev gcc x11vnc xvfb
-# Copy over / clean maiko repo
-COPY . /app/maiko
-RUN rm -rf /app/maiko/linux*
-# Build maiko
-WORKDIR /app/maiko/bin
-RUN ./makeright x
-RUN if [ "$(./osversion)" = "linux" ] && [ "$(./machinetype)" = "x86_64" ]; then ./makeright init; fi
-# Prep for Install Stage
-RUN mv ../$(./osversion).$(./machinetype) ../TRANSFER
-#
-#  Install Maiko Stage
-#
-FROM ubuntu:focal
-ARG BUILD_DATE="not_available"
-ARG RELEASE_TAG="not_available"
-LABEL name="Maiko"
-LABEL description="Virtual machine for Interlisp Medley"
-LABEL url="https://github.com/Interlisp/maiko"
-LABEL build-time=$BUILD_DATE
-LABEL release_tag=$RELEASE_TAG
-ENV MAIKO_RELEASE=$RELEASE_TAG
-ENV MAIKO_BUILD_DATE=$BUILD_DATE
-ARG BUILD_LOCATION=/app/maiko
-ARG INSTALL_LOCATION=/usr/local/interlisp/maiko
-#
-SHELL ["/bin/bash", "-c"]
-USER root:root
-# Copy release files into /usr/local/directories
-COPY --from=builder ${BUILD_LOCATION}/bin/osversion    ${INSTALL_LOCATION}/bin/
-COPY --from=builder ${BUILD_LOCATION}/bin/machinetype  ${INSTALL_LOCATION}/bin/
-COPY --from=builder ${BUILD_LOCATION}/bin/config.guess ${INSTALL_LOCATION}/bin/
-COPY --from=builder ${BUILD_LOCATION}/bin/config.sub   ${INSTALL_LOCATION}/bin/
-COPY --from=builder ${BUILD_LOCATION}/TRANSFER/lde*    ${INSTALL_LOCATION}/TRANSFER/
-RUN  cd ${INSTALL_LOCATION} && mv TRANSFER "$(cd bin && ./osversion).$(cd bin/ && ./machinetype)"
-# Some niceties
-USER root
-WORKDIR /root
-ENTRYPOINT /bin/bash

bin/makefile-cygwin.x86_64-sdl

@@ -0,0 +1,20 @@
+# Options for Linux, Intel x86_64 and X-Window
+
+CC = gcc -m64 $(GCC_CFLAGS) -I/usr/local/include
+#CC = clang -m64 $(CLANG_CFLAGS)
+
+XFILES = $(OBJECTDIR)sdl.o
+
+XFLAGS = -DSDL
+
+# OPTFLAGS is normally -O2.
+OPTFLAGS =  -O2 -g3
+DFLAGS = $(XFLAGS) -DRELEASE=351
+
+LDFLAGS = -lm -L/usr/local/lib -lSDL2
+#
+LDELDFLAGS =
+
+OBJECTDIR = ../$(RELEASENAME)/
+
+default	: ../$(OSARCHNAME)/lde ../$(OSARCHNAME)/ldesdl

bin/makefile-darwin.aarch64-x

@@ -16,8 +16,8 @@ XFILES = $(OBJECTDIR)xmkicon.o \
 XFLAGS = -I/opt/X11/include -DXWINDOW
 
 # OPTFLAGS is normally -O2.
-OPTFLAGS =  -O2
-DEBUGFLAGS = # -DDEBUG -DOPTRACE
+OPTFLAGS = -g -O2
+DEBUGFLAGS = -DARRAYCHECK -DDTDDEBUG # -DDEBUG -DOPTRACE
 DFLAGS = $(DEBUGFLAGS) $(XFLAGS) -DRELEASE=351
 
 LDFLAGS = -L/opt/X11/lib -lX11 -lm

bin/makefile-darwin.x86_64-x

@@ -17,7 +17,7 @@ XFLAGS = -I/opt/X11/include -DXWINDOW
 
 # OPTFLAGS is normally -O2.
 OPTFLAGS =  -O1 -g
-DEBUGFLAGS = # -DDEBUG -DOPTRACE
+DEBUGFLAGS = -DARRAYCHECK -DDTDDEBUG # -DDEBUG -DOPTRACE
 DFLAGS = $(DEBUGFLAGS) $(XFLAGS) -DRELEASE=351
 
 LDFLAGS = -L/opt/X11/lib -lX11 -lm

inc/adr68k.h

@@ -28,11 +28,19 @@
 */
 /**********************************************************************/
 
+#include <execinfo.h>
 #include <stddef.h>
 #include <stdio.h>
 #include "lispemul.h"
 #include "lspglob.h"
 
+static inline void dobacktrace()
+{
+  void* callstack[128];
+  int i, frames = backtrace(callstack, 128);
+  backtrace_symbols_fd(callstack, frames, 2);
+}
+
 static inline LispPTR LAddrFromNative(void *NAddr)
 {
   if ((uintptr_t)NAddr & 1) {
@@ -48,8 +56,9 @@ static inline DLword *NativeAligned2FromLAddr(LispPTR LAddr)
 
 static inline LispPTR *NativeAligned4FromLAddr(LispPTR LAddr)
 {
-  if (LAddr & 1) {
-    printf("Misaligned pointer in NativeAligned4FromLAddr 0x%x\n", LAddr);
+  if (LAddr & 1 || LAddr > 0x0FFFFFFF) {
+    printf("Misaligned/bad pointer in NativeAligned4FromLAddr 0x%x\n", LAddr);
+    dobacktrace();
   }
   return (void *)(Lisp_world + LAddr);
 }

src/gcfinal.c

@@ -97,6 +97,18 @@ struct buf {
 };
 #endif /* BIGVM */
 #else
+#ifdef BIGVM
+struct buf {
+  LispPTR filepage;
+  LispPTR vmempage;
+  LispPTR buffernext;
+  unsigned sysnext : 28;
+  unsigned unused : 1;
+  unsigned iodirty : 1;
+  unsigned usermapped : 1;
+  unsigned noreference : 1;
+};
+#else
 struct buf {
   LispPTR filepage;
   LispPTR vmempage;
@@ -107,6 +119,7 @@ struct buf {
   unsigned usermapped : 1;
   unsigned noreference : 1;
 };
+#endif /* BIGVM */
 #endif /* BYTESWAP */
 
 /************* The following procedure is common !! **************************/
@@ -143,8 +156,10 @@ LispPTR findptrsbuffer(LispPTR ptr) {
   while (LAddrFromNative(bptr) != NIL) {
     if (ptr == bptr->vmempage)
       return (LAddrFromNative(bptr));
-    else
+    else {
+      if (bptr->sysnext & 0xF0000000) printf("findptrsbuffer: would have failed %p 0x%X\n", bptr, bptr->sysnext);
       bptr = (struct buf *)NativeAligned4FromLAddr(bptr->sysnext);
+    }
   }
   return (NIL);
 }
@@ -192,8 +207,6 @@ LispPTR checkarrayblock(LispPTR base, LispPTR free, LispPTR onfreelist) {
   {
     bbase = (struct arrayblock *)NativeAligned4FromLAddr(base);
     btrailer = (struct arrayblock *)NativeAligned4FromLAddr(Trailer(base, bbase));
-    bfwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->fwd);
-    bbwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->bkwd);
     if (bbase->password != ARRAYBLOCKPASSWORD) {
       printarrayblock(base);
       error("ARRAYBLOCK password wrong\n");
@@ -215,7 +228,10 @@ LispPTR checkarrayblock(LispPTR base, LispPTR free, LispPTR onfreelist) {
     } else if (!onfreelist || (bbase->arlen < MINARRAYBLOCKSIZE))
       /* Remaining tests only for free list. */
       return (NIL);
-    else if ((bbwd->fwd != base) || (bfwd->bkwd != base)) {
+
+    bfwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->fwd);
+    bbwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->bkwd);
+    if ((bbwd->fwd != base) || (bfwd->bkwd != base)) {
       error("ARRAYBLOCK links fouled\n");
     } else {
       fbl = FreeBlockChainN(bbase->arlen);

src/mkcell.c

@@ -72,7 +72,7 @@ retry:
     if (917505 == *(LispPTR *)ptr) error("N_OP_createcell E0001 error");
     /* replace dtd_free with newcell's top DLword (it may keep next chain)*/
     dtd68k->dtd_free = (*((LispPTR *)ptr)) & POINTERMASK;
-    if (dtd68k->dtd_free & 0x8000001) error("bad entry on free chain.");
+    if (dtd68k->dtd_free & 0x8000001) error("bad entry on free chain(1).");
 
     dtd68k->dtd_oldcnt++;
 
@@ -84,7 +84,7 @@ retry:
     return (tos);
   } else {
     dtd68k->dtd_free = initmdspage(alloc_mdspage(dtd68k->dtd_typeentry), dtd68k->dtd_size, NIL);
-    if (dtd68k->dtd_free & 0x8000000) error("bad entry on free chain.");
+    if (dtd68k->dtd_free & 0x8000000) error("bad entry on free chain(2).");
     goto retry;
   }
 
@@ -119,7 +119,7 @@ retry:
 
     /* replace dtd_free with newcell's top DLword (it may keep next chain)*/
     dtd68k->dtd_free = (*((LispPTR *)ptr)) & POINTERMASK;
-    if (dtd68k->dtd_free & 0x8000000) error("bad entry on free chain.");
+    if (dtd68k->dtd_free & 0x8000000) error("bad entry on free chain(3).");
 
 #ifdef DTDDEBUG
     if ((dtd68k->dtd_free != 0) && (type != GetTypeNumber(dtd68k->dtd_free)))
@@ -144,7 +144,7 @@ retry:
 
   } else {
     dtd68k->dtd_free = initmdspage(alloc_mdspage(dtd68k->dtd_typeentry), dtd68k->dtd_size, NIL);
-    if (dtd68k->dtd_free & 0x8000000) error("bad entry on free chain.");
+    if (dtd68k->dtd_free & 0x8000000) error("bad entry on free chain(4).");
 
 #ifdef DTDDEBUG
     check_dtd_chain(type);