diff --git a/imgui.cpp b/imgui.cpp
index fdd2b8c..56477fe 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -17475,7 +17475,7 @@
 
     ImGuiContext& g = *GImGui;
     const ImGuiID id = window->GetID(label);
-    const ImVec2 label_size = CalcTextSize(label, NULL, true);
+    const ImVec2 label_size = CalcTextSize(label, true);
     ImVec2 pos = window->DC.CursorPos + ImVec2(0.0f, window->DC.CurrLineTextBaseOffset);
     ImVec2 size = ImVec2(label_size.x + g.Style.FramePadding.x * 2.0f, label_size.y);
 
diff --git a/imgui.h b/imgui.h
index b80d236..e889aaa 100644
--- a/imgui.h
+++ b/imgui.h
@@ -1198,6 +1198,10 @@
     inline IM_FMTLIST(3) bool    TreeNodeExV(const char* str_id, ImGuiTreeNodeFlags flags, const char* fmt, va_list args) { return TreeNodeEx(ImStrv(str_id), flags, fmt, args); }
     inline               void    TreePush(const char* str_id)                                                             { TreePush(ImStrv(str_id)); }
 IM_MSVC_RUNTIME_CHECKS_RESTORE
+
+    // Detect misuses (#9321)
+    // FIXME-IMSTR: Validate that syntax is ok for our minimum target.
+    ImVec2 CalcTextSize(ImStrv, const char*, bool hide_text_after_double_hash = false, float wrap_width = -1.0f) = delete;
 }
 
 //-----------------------------------------------------------------------------
diff --git a/imgui_tables.cpp b/imgui_tables.cpp
index a02e3dd..a05f847 100644
--- a/imgui_tables.cpp
+++ b/imgui_tables.cpp
@@ -3271,7 +3271,7 @@
     for (int column_n = 0; column_n < table->ColumnsCount; column_n++)
         if (IM_BITARRAY_TESTBIT(table->EnabledMaskByIndex, column_n))
             if (table->Columns[column_n].Flags & ImGuiTableColumnFlags_AngledHeader)
-                width = ImMax(width, CalcTextSize(TableGetColumnName(table, column_n), NULL, true).x);
+                width = ImMax(width, CalcTextSize(TableGetColumnName(table, column_n), true).x);
     return width + g.Style.CellPadding.y * 2.0f; // Swap padding
 }
 
@@ -3682,7 +3682,7 @@
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
 
-    ImVec2 label_size = CalcTextSize(label, NULL, true);
+    ImVec2 label_size = CalcTextSize(label, true);
     ImGuiMenuColumns* offsets = &window->DC.MenuColumns;
     float checkmark_w = IM_TRUNC(g.FontSize * 1.20f);
     float min_w = offsets->DeclColumns(0.0f, label_size.x, 0.0f, checkmark_w); // Feedback for next frame
diff --git a/imgui_widgets.cpp b/imgui_widgets.cpp
index b9834e7..36846c3 100644
--- a/imgui_widgets.cpp
+++ b/imgui_widgets.cpp
@@ -1520,7 +1520,6 @@
 
     ImGuiContext& g = *GImGui;
     const ImGuiID id = window->GetID(label);
-
     const ImStrv label_for_display(label.Begin, FindRenderedTextEnd(label));
     ImVec2 pos(window->DC.CursorPos.x, window->DC.CursorPos.y + window->DC.CurrLineTextBaseOffset);
     ImVec2 size = CalcTextSize(label_for_display, false);
@@ -5664,14 +5663,14 @@
 
                 float rect_width = 0.0f;
                 if (line_selected_begin < line_selected_end)
-                    rect_width += CalcTextSize(line_selected_begin, line_selected_end).x;
+                    rect_width += CalcTextSize(ImStrv(line_selected_begin, line_selected_end)).x;
                 if (text_selected_begin <= p_eol && text_selected_end > p_eol && !p_eol_is_wrap)
                     rect_width += bg_eol_width; // So we can see selected empty lines
                 if (rect_width == 0.0f)
                     continue;
 
                 ImRect rect;
-                rect.Min.x = draw_pos.x - draw_scroll.x + CalcTextSize(p, line_selected_begin).x;
+                rect.Min.x = draw_pos.x - draw_scroll.x + CalcTextSize(ImStrv(p, line_selected_begin)).x;
                 rect.Min.y = draw_pos.y - draw_scroll.y + line_n * g.FontSize;
                 rect.Max.x = rect.Min.x + rect_width;
                 rect.Max.y = rect.Min.y + bg_offy_dn + g.FontSize;
@@ -5684,7 +5683,7 @@
 
     // Find render position for right alignment (single-line only)
     if (g.ActiveId != id && (flags & ImGuiInputTextFlags_ElideLeft) && !render_cursor && !render_selection)
-        draw_pos.x = ImMin(draw_pos.x, frame_bb.Max.x - CalcTextSize(buf_display, NULL).x - style.FramePadding.x);
+        draw_pos.x = ImMin(draw_pos.x, frame_bb.Max.x - CalcTextSize(buf_display).x - style.FramePadding.x);
     //draw_scroll.x = state->Scroll.x; // Preserve scroll when inactive?
 
     // Render text