Add assembly constraints to disable some overly aggressive GCC optimizations

sandbox/linux/seccomp/trusted_thread.cc

 #include "sandbox_impl.h"
 #include "syscall_table.h"
 
 namespace playground {
 
 void Sandbox::createTrustedThread(int processFdPub, int cloneFdPub,
                                   SecureMem::Args* secureMem) {
   SecureMem::Args args                  = { { { { { 0 } } } } };
   args.self                             = &args;
   args.newSecureMem                     = secureMem;
@@ skipping 568 matching lines @@
       ".pushsection \".rodata\"\n"
   "100:.ascii \"Sandbox violation detected, program aborted\\n\"\n"
   "101:\n"
       ".popsection\n"
 
   "999:pop  %%rbp\n"
       "pop  %%rbx\n"
       :
       : "g"(&args)
       : "rax", "rcx", "rdx", "rdi", "rsi", "r8", "r9", "r10", "r11", "r12",
-        "r13", "r14", "r15"
+        "r13", "r14", "r15", "rsp", "memory"
 #elif defined(__i386__)
   struct user_desc u;
   u.entry_number    = (typeof u.entry_number)-1;
   u.base_addr       = 0;
   u.limit           = 0xfffff;
   u.seg_32bit       = 1;
   u.contents        = 0;
   u.read_exec_only  = 0;
   u.limit_in_pages  = 1;
   u.seg_not_present = 0;
@@ skipping 590 matching lines @@
 
       ".pushsection \".rodata\"\n"
   "100:.ascii \"Sandbox violation detected, program aborted\\n\"\n"
   "101:\n"
       ".popsection\n"
 
   "999:pop  %%ebp\n"
       "pop  %%ebx\n"
       :
       : "g"(&args)
-      : "eax", "ecx", "edx", "edi", "esi"
+      : "eax", "ecx", "edx", "edi", "esi", "esp", "memory"
 #else
 #error Unsupported target platform
 #endif
 );
 }
 
 } // namespace