Builds with gcc 7.0 fail with:

../test-skeleton.c: In function ‘legacy_test_function’:
cc1: error: assuming signed overflow does not occur when \
assuming that (X - c) <= X is always true [-Werror=strict-overflow]

Ignoring this warning until the test or compiler is adjusted.
Disabled with -Wno-strict-overflow. Attempted -Wstrict-overflow=1,
but it still results in the same warning.

Index: glibc-2.24-661-g5653ab1/string/Makefile
===================================================================
--- glibc-2.24-661-g5653ab1.orig/string/Makefile
+++ glibc-2.24-661-g5653ab1/string/Makefile
@@ -71,7 +71,9 @@ include ../Rules
 CFLAGS-inl-tester.c = -fno-builtin
 CFLAGS-noinl-tester.c = -fno-builtin
 CFLAGS-tst-strlen.c = -fno-builtin
-CFLAGS-stratcliff.c = -fno-builtin
+# Added '-Wno-strict-overflow' for gcc 7.0 until the test or compiler
+# is adjusted.
+CFLAGS-stratcliff.c = -fno-builtin -Wno-strict-overflow
 CFLAGS-test-ffs.c = -fno-builtin
 CFLAGS-tst-inlcall.c = -fno-builtin
 CFLAGS-tst-xbzero-opt.c = -O3
Index: glibc-2.24-661-g5653ab1/wcsmbs/Makefile
===================================================================
--- glibc-2.24-661-g5653ab1.orig/wcsmbs/Makefile
+++ glibc-2.24-661-g5653ab1/wcsmbs/Makefile
@@ -102,3 +102,7 @@ CPPFLAGS += $(libio-mtsafe)
 CPPFLAGS-wcstold_l.c = -I../stdlib
 
 $(objpfx)tst-wcstod-nan-locale: $(libm)
+
+# Added '-Wno-strict-overflow' for gcc 7.0 until the test or compiler
+# is adjusted.
+CFLAGS-wcsatcliff.c = -Wno-strict-overflow