+ update sgeo-minimal merge strategy

blueprints/sgeo-min-7.1.13-avx2/000.bash

@@ -7,7 +7,10 @@ echo 'https://github.com/Sgeo/p373r-sgeo-minimal/tree/sgeo_min_vr_7.1.9' > repo/
 pushd repo/viewer
     git remote add sgeo-minimal https://github.com/Sgeo/p373r-sgeo-minimal
     git fetch sgeo-minimal sgeo_min_vr_7.1.9
-    git -c user.email=CITEST -c user.name=CITEST merge --no-edit sgeo-minimal/sgeo_min_vr_7.1.9
+    git checkout sgeo-minimal/sgeo_min_vr_7.1.9 -- indra/newview/llviewerVR.\*
+    bash $fsvr_dir/util/git_union_merge.bash sgeo-minimal/sgeo_min_vr_7.1.9 indra/newview/llviewerdisplay.cpp
+    # git diff -U0 ...sgeo-minimal/sgeo_min_vr_7.1.9 | patch -p1 --merge
+    # git -c user.email=CITEST -c user.name=CITEST merge --no-edit sgeo-minimal/sgeo_min_vr_7.1.9
     # || {
     #   dos2unix --to-stdout $nunja_dir/sgeo-minimal.7.1.10.mergeconflict-fixes.patch | patch -p1
     #   git add -u
@@ -53,3 +56,4 @@ EOF
   git diff
   # git -C repo/viewer diff
 popd
+

blueprints/sgeo-min-7.1.13-noavx/000.bash

@@ -7,7 +7,10 @@ echo 'https://github.com/Sgeo/p373r-sgeo-minimal/tree/sgeo_min_vr_7.1.9' > repo/
 pushd repo/viewer
     git remote add sgeo-minimal https://github.com/Sgeo/p373r-sgeo-minimal
     git fetch sgeo-minimal sgeo_min_vr_7.1.9
-    git -c user.email=CITEST -c user.name=CITEST merge --no-edit sgeo-minimal/sgeo_min_vr_7.1.9
+    git checkout sgeo-minimal/sgeo_min_vr_7.1.9 -- indra/newview/llviewerVR.\*
+    bash $fsvr_dir/util/git_union_merge.bash sgeo-minimal/sgeo_min_vr_7.1.9 indra/newview/llviewerdisplay.cpp
+    # git diff -U0 ...sgeo-minimal/sgeo_min_vr_7.1.9 | patch -p1 --merge
+    # git -c user.email=CITEST -c user.name=CITEST merge --no-edit sgeo-minimal/sgeo_min_vr_7.1.9
     # || {
     #   dos2unix --to-stdout $nunja_dir/sgeo-minimal.7.1.10.mergeconflict-fixes.patch | patch -p1
     #   git add -u

util/git_union_merge.bash

@@ -0,0 +1,106 @@
+#!/bin/bash
+#
+# git-union-merge.sh
+#
+# A script to perform a targeted 3-way "union" merge on a single file. It can be
+# run directly as a command-line tool or sourced into another script to provide
+# the `git_union_merge` helper function.
+#
+# This is designed to preemptively resolve predictable, non-overlapping conflicts
+# (like two branches adding an #include in the same general area) without leaving
+# conflict markers. It's intended for ephemeral CI/CD environments where persistent
+# git config changes are impractical.
+#
+# USAGE (as a command-line tool):
+#   ./git-union-merge.sh <mod-branch> <file-path>
+#
+# USAGE (sourced in another script):
+#   source ./git-union-merge.sh
+#   git_union_merge <mod-branch> <file-path>
+#
+
+# Exit immediately if a command exits with a non-zero status.
+# We set this within the function to avoid affecting the sourcing shell.
+
+# --- Helper Function ---
+# Encapsulates the core logic of the script.
+git_union_merge() {
+    # Use a subshell or set -e locally to avoid exiting the parent script on error
+    (
+        set -e
+
+        # --- Argument Validation ---
+        if [ "$#" -ne 2 ]; then
+            echo "Usage: git_union_merge <mod-branch> <file-path>" >&2
+            echo "Example: git_union_merge sidestream/sgeo_min_vr_7.1.9 indra/newview/llviewerdisplay.cpp" >&2
+            return 1
+        fi
+
+        local MOD_BRANCH="$1"
+        local FILE_PATH="$2"
+
+        # --- Pre-flight Checks ---
+        if ! git rev-parse --is-inside-work-tree > /dev/null 2>&1; then
+            echo "Error: Not inside a Git repository." >&2
+            return 1
+        fi
+
+        if [ ! -f "$FILE_PATH" ]; then
+            echo "Error: File not found at path: ${FILE_PATH}" >&2
+            return 1
+        fi
+
+        echo "-> Starting union merge for: ${FILE_PATH}" >&2
+
+        # --- Define File Versions ---
+        # OURS is the version currently on disk in the working directory.
+        local UPSTREAM_BRANCH
+        UPSTREAM_BRANCH=$(git rev-parse HEAD)
+        local OURS_FILE="${FILE_PATH}"
+
+        # --- Find Common Ancestor (BASE) ---
+        echo "-> Finding common ancestor between HEAD (${UPSTREAM_BRANCH:0:7}) and ${MOD_BRANCH}..." >&2
+        local MERGE_BASE_COMMIT
+        MERGE_BASE_COMMIT=$(git merge-base "${UPSTREAM_BRANCH}" "${MOD_BRANCH}")
+
+        if [ -z "$MERGE_BASE_COMMIT" ]; then
+            echo "Error: Could not find a merge base between ${UPSTREAM_BRANCH} and ${MOD_BRANCH}." >&2
+            return 1
+        fi
+        echo "-> Found common ancestor commit: ${MERGE_BASE_COMMIT:0:7}" >&2
+
+        # --- Isolate File Versions into Temporary Files ---
+        local BASE_FILE THEIRS_FILE MERGED_FILE
+        BASE_FILE=$(mktemp)
+        THEIRS_FILE=$(mktemp)
+        MERGED_FILE=$(mktemp)
+        # Set up a trap to ensure temporary files are cleaned up on exit, error, or interrupt.
+        trap 'rm -f "${BASE_FILE}" "${THEIRS_FILE}" "${MERGED_FILE}"' RETURN
+
+        echo "-> Extracting BASE and THEIRS versions to temporary files..." >&2
+        git show "${MERGE_BASE_COMMIT}:${FILE_PATH}" > "${BASE_FILE}"
+        git show "${MOD_BRANCH}:${FILE_PATH}" > "${THEIRS_FILE}"
+
+        # --- Perform the Union Merge ---
+        echo "-> Running 'git merge-file --union'..." >&2
+        if git merge-file -p --union "${OURS_FILE}" "${BASE_FILE}" "${THEIRS_FILE}" > "${MERGED_FILE}"; then
+            mv "${MERGED_FILE}" "${OURS_FILE}"
+            echo "✅ Success! File '${FILE_PATH}' merged cleanly." >&2
+        else
+            echo "❌ Error: A hard conflict was detected in '${FILE_PATH}'. Manual resolution required." >&2
+            echo "-> Conflicting output can be found in: ${MERGED_FILE}" >&2
+            # Let the subshell exit with an error code.
+            return 1
+        fi
+    )
+}
+
+# --- Script Entrypoint (like Python's `if __name__ == "__main__":`) ---
+# This block only runs when the script is executed directly, not when sourced.
+# It allows the script to be used as a standalone tool.
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    # When executed, call the main function with all command-line arguments.
+    set -e
+    git_union_merge "$@"
+fi
+