diff --git a/build-aux/syntax-check.mk b/build-aux/syntax-check.mk
index 9407581d0e..a8c9153b20 100644
--- a/build-aux/syntax-check.mk
+++ b/build-aux/syntax-check.mk
@@ -1549,7 +1549,7 @@ sc_spacing-check:
 	  { echo '$(ME): incorrect formatting' 1>&2; exit 1; }
 
 sc_mock-noinline:
-	$(AM_V_GEN)$(VC_LIST_EXCEPT) | $(GREP) '\.[ch]$$' | $(RUNUTF8) xargs \
+	$(AM_V_GEN)$(VC_LIST_EXCEPT) | $(GREP) '\.[ch]$$' | $(RUNUTF8) \
 	$(PYTHON) $(top_srcdir)/scripts/mock-noinline.py
 
 sc_header-ifdef:
diff --git a/scripts/mock-noinline.py b/scripts/mock-noinline.py
index 712550cb7a..13c296603d 100644
--- a/scripts/mock-noinline.py
+++ b/scripts/mock-noinline.py
@@ -63,7 +63,7 @@ def scan_overrides(filename):
                     mocked[name] = "%s:%d" % (filename, lineno)
 
 
-for filename in sys.argv[1:]:
+for filename in sys.stdin.readlines():
     if filename.endswith(".h"):
         scan_annotations(filename)
     elif filename.endswith("mock.c"):