diff --git a/source/build/src/baselayer.cpp b/source/build/src/baselayer.cpp
index 7b3a29264677f56c428c6cdcf339c3b88f231e8e..afba0ab0e26a2538a01a1ae357524ea1ce99eb21 100644
--- a/source/build/src/baselayer.cpp
+++ b/source/build/src/baselayer.cpp
@@ -65,11 +65,10 @@ int initprintf(const char *f, ...)
         va_list va;
         buf = (char *)Xrealloc(buf, (size <<= 1));
         va_start(va, f);
-        len = Bvsnprintf(buf, size-1, f, va);
+        len = Bvsnprintf(buf, size, f, va);
         va_end(va);
-    } while ((unsigned)len > size-1);
+    } while ((unsigned)len >= size);
 
-    buf[len] = 0;
     initputs(buf);
     Xfree(buf);
 
diff --git a/source/build/src/glbuild.cpp b/source/build/src/glbuild.cpp
index dfd91b070d6a33ef90882187bc33cf0d84c318a6..bad2eafab0b6d91135e56c57b0d232b8e5bf76ba 100644
--- a/source/build/src/glbuild.cpp
+++ b/source/build/src/glbuild.cpp
@@ -45,11 +45,10 @@ void buildgl_outputDebugMessage(uint8_t severity, const char* format, ...)
         va_list va;
         buf = (char *)Xrealloc(buf, (size <<= 1));
         va_start(va, format);
-        len = Bvsnprintf(buf, size-1, format, va);
+        len = Bvsnprintf(buf, size, format, va);
         va_end(va);
-    } while ((unsigned)len > size-1);
+    } while ((unsigned)len >= size);
 
-    buf[len] = 0;
     glDebugMessageInsertARB(GL_DEBUG_SOURCE_APPLICATION_ARB,
                             GL_DEBUG_TYPE_OTHER_ARB,
                             0,
diff --git a/source/build/src/osd.cpp b/source/build/src/osd.cpp
index 36ed4eb3453ae96c3bfd3c68092e353677ab9a55..7554cb1fbe16b3d8952f1fcf70072269ccfb2523 100644
--- a/source/build/src/osd.cpp
+++ b/source/build/src/osd.cpp
@@ -1686,11 +1686,9 @@ int OSD_Printf(const char *f, ...)
         va_list va;
         buf = (char *)Xrealloc(buf, (size <<= 1));
         va_start(va, f);
-        len = Bvsnprintf(buf, size-1, f, va);
+        len = Bvsnprintf(buf, size, f, va);
         va_end(va);
-    } while ((unsigned)len > size-1);
-    
-    buf[len] = 0;
+    } while ((unsigned)len >= size);
 
     OSD_Puts(buf);