diff --git a/Process.c b/Process.c
index 7b61de0c9..4cdd8cb84 100644
--- a/Process.c
+++ b/Process.c
@@ -824,9 +824,9 @@ void Process_writeField(const Process* this, RichString* str, ProcessField field
       char* buf = buffer;
       const bool lastItem = (this->indent < 0);
 
-      for (int indent = (this->indent < 0 ? -this->indent : this->indent); indent > 1; indent >>= 1) {
+      for (uint64_t indent = (this->indent < 0 ? -this->indent : this->indent); indent > 1; indent >>= 1) {
          int written, ret;
-         if (indent & 1) {
+         if (indent & 1U) {
             ret = xSnprintf(buf, n, "%s  ", CRT_treeStr[TREE_STR_VERT]);
          } else {
             ret = xSnprintf(buf, n, "   ");
diff --git a/Process.h b/Process.h
index a1ca50fb5..613bbb046 100644
--- a/Process.h
+++ b/Process.h
@@ -242,7 +242,7 @@ typedef struct Process_ {
    /*
     * Internal state for tree-mode.
     */
-   int indent;
+   int64_t indent;
    unsigned int tree_depth;
 
    /* Has no known parent process */
diff --git a/ProcessList.c b/ProcessList.c
index bbaddd862..30a1f1ad3 100644
--- a/ProcessList.c
+++ b/ProcessList.c
@@ -199,7 +199,7 @@ static void ProcessList_removeIndex(ProcessList* this, const Process* p, int idx
    assert(Vector_countEquals(this->processes, Hashtable_count(this->processTable)));
 }
 
-static void ProcessList_buildTreeBranch(ProcessList* this, pid_t pid, int level, int indent, bool show) {
+static void ProcessList_buildTreeBranch(ProcessList* this, pid_t pid, unsigned int level, int64_t indent, bool show) {
    // On OpenBSD the kernel thread 'swapper' has pid 0.
    // Do not treat it as root of any tree.
    if (pid == 0)
@@ -239,7 +239,7 @@ static void ProcessList_buildTreeBranch(ProcessList* this, pid_t pid, int level,
 
       Vector_add(this->displayList, process);
 
-      int nextIndent = indent | (1 << level);
+      int64_t nextIndent = indent | ((int64_t)1 << MINIMUM(level, sizeof(process->indent) * 8 - 2));
       ProcessList_buildTreeBranch(this, process->pid, level + 1, (i < lastShown) ? nextIndent : indent, process->show && process->showChildren);
       if (i == lastShown) {
          process->indent = -nextIndent;