diff --git a/bin/install_megadrivers.py b/bin/install_megadrivers.py
index 216f6999feb..ed2afe91d2c 100644
--- a/bin/install_megadrivers.py
+++ b/bin/install_megadrivers.py
@@ -41,7 +41,7 @@ def main():
     parser.add_argument('megadriver')
     parser.add_argument('libdir')
     parser.add_argument('drivers', nargs='+')
-    parser.add_argument('--megadriver_libdir')
+    parser.add_argument('--megadriver-libdir')
     args = parser.parse_args()
 
     to = resolve_libdir(args.libdir)
diff --git a/src/gallium/targets/dri/meson.build b/src/gallium/targets/dri/meson.build
index 42af4c44911..28d090ba206 100644
--- a/src/gallium/targets/dri/meson.build
+++ b/src/gallium/targets/dri/meson.build
@@ -94,7 +94,7 @@ if with_gallium_va or with_gallium_vdpau
       libgallium_dri.full_path(),
       va_drivers_path,
       va_drivers,
-      '--megadriver_libdir', get_option('libdir'),
+      '--megadriver-libdir', get_option('libdir'),
       install_tag : 'runtime',
     )
   endif
@@ -105,7 +105,7 @@ if with_gallium_va or with_gallium_vdpau
       libgallium_dri.full_path(),
       vdpau_drivers_path,
       vdpau_drivers,
-      '--megadriver_libdir', get_option('libdir'),
+      '--megadriver-libdir', get_option('libdir'),
       install_tag : 'runtime',
     )
   endif