diff --git a/mkspecs/features/unix/gdb_dwarf_index.prf b/mkspecs/features/unix/gdb_dwarf_index.prf
index 7771ed4f88..e3f79cdac6 100644
--- a/mkspecs/features/unix/gdb_dwarf_index.prf
+++ b/mkspecs/features/unix/gdb_dwarf_index.prf
@@ -4,12 +4,13 @@
         QMAKE_GDB_INDEX = { test -z \"$(DESTDIR)\" || cd \"$(DESTDIR)\"; } &&
         QMAKE_GDB_DIR = .
     } else {
-        QMAKE_GDB_DIR = $(DESTDIR)
+        QMAKE_GDB_INDEX = { test -n \"$(DESTDIR)\" && DESTDIR=\"$(DESTDIR)\" || DESTDIR=.; } &&
+        QMAKE_GDB_DIR = \$\$DESTDIR
     }
 
     QMAKE_GDB_INDEX += \
       test \$\$(gdb --version | sed -e \'s,[^0-9]\\+\\([0-9]\\)\\.\\([0-9]\\).*,\\1\\2,;q\') -gt 72 && \
-      gdb --nx --batch --quiet -ex \'set confirm off\' -ex \'save gdb-index $$QMAKE_GDB_DIR\' -ex quit \'$(TARGET)\'  && \
+      gdb --nx --batch --quiet -ex \'set confirm off\' -ex \"save gdb-index $$QMAKE_GDB_DIR\" -ex quit \'$(TARGET)\'  && \
       test -f $(TARGET).gdb-index && \
       $$QMAKE_OBJCOPY --add-section \'.gdb_index=$(TARGET).gdb-index\' --set-section-flags \'.gdb_index=readonly\' \'$(TARGET)\' \'$(TARGET)\' && \
       $$QMAKE_DEL_FILE $(TARGET).gdb-index || true