nixpkgs/pkgs/development/compilers/gcc/res_state-not-declared.patch

diff --git a/libsanitizer/tsan/tsan_platform_linux.cc b/libsanitizer/tsan/tsan_platform_linux.cc
index fe69430..49f5270 100644
--- a/libsanitizer/tsan/tsan_platform_linux.cc
+++ b/libsanitizer/tsan/tsan_platform_linux.cc
@@ -351,7 +351,7 @@ bool IsGlobalVar(uptr addr) {
 // closes within glibc. The code is a pure hack.
 int ExtractResolvFDs(void *state, int *fds, int nfd) {
   int cnt = 0;
-  __res_state *statp = (__res_state*)state;
+  struct __res_state *statp = (struct __res_state*)state;
   for (int i = 0; i < MAXNS && cnt < nfd; i++) {
     if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1)
       fds[cnt++] = statp->_u._ext.nssocks[i];