libc: add clang FORTIFY support
This patch adds clang-style FORTIFY to Bionic. For more information on
FORTIFY, please see https://goo.gl/8HS2dW . This implementation works
for versions of clang that don't support diagnose_if, so please see the
"without diagnose_if" sections. We plan to swap to a diagnose_if-based
FORTIFY later this year (since it doesn't really add any features; it
just simplifies the implementation a lot, and it gives us much prettier
diagnostics)
Bug: 32073964
Test: Builds on angler, bullhead, marlin, sailfish. Bionic CTS tests
pass on Angler and Bullhead.
Change-Id: I607aecbeee81529709b1eee7bef5b0836151eb2b
diff --git a/libc/bionic/getcwd.cpp b/libc/bionic/getcwd.cpp
index bcd6a57..c2a7e23 100644
--- a/libc/bionic/getcwd.cpp
+++ b/libc/bionic/getcwd.cpp
@@ -34,7 +34,7 @@
extern "C" int __getcwd(char* buf, size_t size);
-char* getcwd(char* buf, size_t size) {
+char* getcwd(char* buf, size_t size) __overloadable {
// You can't specify size 0 unless you're asking us to allocate for you.
if (buf != NULL && size == 0) {
errno = EINVAL;