diff --git a/lib/bash/std/lib_std.sh b/lib/bash/std/lib_std.sh
index 8fd06e6..b0103f6 100644
--- a/lib/bash/std/lib_std.sh
+++ b/lib/bash/std/lib_std.sh
@@ -1769,13 +1769,25 @@ __std_make_temp_path__() {
     fi
 
     __std_temp_root="${TMPDIR:-/tmp}"
-    __std_temp_root="${__std_temp_root%/}"
+    if [[ "$__std_temp_root" != /* ]]; then
+        if ! __std_temp_root="$(cd -- "$__std_temp_root" 2>/dev/null && pwd -P)"; then
+            log_error -l base_bash_libs.std "$__std_temp_helper_name: TMPDIR is not a directory: ${TMPDIR:-/tmp}"
+            return 1
+        fi
+    fi
+    while [[ "$__std_temp_root" != "/" && "$__std_temp_root" == */ ]]; do
+        __std_temp_root="${__std_temp_root%/}"
+    done
     if [[ -z "$__std_temp_root" || ! -d "$__std_temp_root" ]]; then
         log_error -l base_bash_libs.std "$__std_temp_helper_name: TMPDIR is not a directory: ${TMPDIR:-/tmp}"
         return 1
     fi
 
-    __std_temp_template="$__std_temp_root/$__std_temp_prefix.XXXXXXXXXX"
+    if [[ "$__std_temp_root" == "/" ]]; then
+        __std_temp_template="/$__std_temp_prefix.XXXXXXXXXX"
+    else
+        __std_temp_template="$__std_temp_root/$__std_temp_prefix.XXXXXXXXXX"
+    fi
     if [[ "$__std_temp_path_kind" == "dir" ]]; then
         __std_temp_path="$(mktemp -d "$__std_temp_template" 2>/dev/null)" || {
             log_error -l base_bash_libs.std "$__std_temp_helper_name: failed to create temporary directory."
diff --git a/lib/bash/std/tests/lib_std.bats b/lib/bash/std/tests/lib_std.bats
index 7e0a739..44e6640 100644
--- a/lib/bash/std/tests/lib_std.bats
+++ b/lib/bash/std/tests/lib_std.bats
@@ -2100,6 +2100,59 @@ EOF
     [ ! -e "$created_path" ]
 }
 
+@test "std_make_temp_file accepts TMPDIR=/" {
+    local script="$TEST_TMPDIR/temp-file-root.sh"
+    local path_file="$TEST_TMPDIR/temp-file-root.path"
+    local created_path
+
+    create_script "$script" <<EOF
+#!/usr/bin/env bash
+source "$STDLIB_PATH"
+TMPDIR=/
+mktemp() {
+    [[ "\$1" == "/root-temp.XXXXXXXXXX" ]] || return 44
+    : > "$TEST_TMPDIR/root-temp-file"
+    printf '%s\n' "$TEST_TMPDIR/root-temp-file"
+}
+std_make_temp_file temp_file root-temp
+[[ -f "\$temp_file" ]] || exit 44
+printf '%s\n' "\$temp_file" > "$path_file"
+EOF
+
+    bats_run bash "$script"
+
+    [ "$status" -eq 0 ]
+    created_path="$(cat "$path_file")"
+    [ "$created_path" = "$TEST_TMPDIR/root-temp-file" ]
+    [ ! -e "$created_path" ]
+}
+
+@test "std_make_temp_file resolves relative and trailing-slash TMPDIR values" {
+    local script="$TEST_TMPDIR/temp-file-relative.sh"
+    local temp_root="$TEST_TMPDIR/temp-relative-root"
+    local path_file="$TEST_TMPDIR/temp-file-relative.path"
+    local created_path expected_root
+
+    mkdir -p "$temp_root"
+    create_script "$script" <<EOF
+#!/usr/bin/env bash
+source "$STDLIB_PATH"
+cd "$TEST_TMPDIR"
+TMPDIR="$(basename "$temp_root")///"
+std_make_temp_file temp_file relative-temp
+[[ -f "\$temp_file" ]] || exit 44
+printf '%s\n' "\$temp_file" > "$path_file"
+EOF
+
+    bats_run bash "$script"
+
+    [ "$status" -eq 0 ]
+    created_path="$(cat "$path_file")"
+    expected_root="$(cd "$temp_root" && pwd -P)"
+    [[ "$created_path" == "$expected_root"/relative-temp.* ]]
+    [ ! -e "$created_path" ]
+}
+
 @test "std_make_temp_dir creates a directory under TMPDIR and cleans it up" {
     local script="$TEST_TMPDIR/temp-dir.sh"
     local temp_root="$TEST_TMPDIR/temp-dir-root"