Bug: C stack overflow with coroutines
'coroutine.resume' did not increment counter of C calls when
continuing execution after a protected error (that is,
while running 'precover').
diff --git a/ldo.c b/ldo.c
index d0edc8b..66f8903 100644
--- a/ldo.c
+++ b/ldo.c
@@ -759,11 +759,10 @@
StkId firstArg = L->top - n; /* first argument */
CallInfo *ci = L->ci;
if (L->status == LUA_OK) /* starting a coroutine? */
- ccall(L, firstArg - 1, LUA_MULTRET, 1); /* just call its body */
+ ccall(L, firstArg - 1, LUA_MULTRET, 0); /* just call its body */
else { /* resuming from previous yield */
lua_assert(L->status == LUA_YIELD);
L->status = LUA_OK; /* mark that it is running (again) */
- luaE_incCstack(L); /* control the C stack */
if (isLua(ci)) { /* yielded inside a hook? */
L->top = firstArg; /* discard arguments */
luaV_execute(L, ci); /* just continue running Lua code */
@@ -814,6 +813,9 @@
else if (L->status != LUA_YIELD) /* ended with errors? */
return resume_error(L, "cannot resume dead coroutine", nargs);
L->nCcalls = (from) ? getCcalls(from) : 0;
+ if (getCcalls(L) >= LUAI_MAXCCALLS)
+ return resume_error(L, "C stack overflow", nargs);
+ L->nCcalls++;
luai_userstateresume(L, nargs);
api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs);
status = luaD_rawrunprotected(L, resume, &nargs);
diff --git a/testes/cstack.lua b/testes/cstack.lua
index 213d15d..ca76c87 100644
--- a/testes/cstack.lua
+++ b/testes/cstack.lua
@@ -103,6 +103,20 @@
end
+do -- bug in 5.4.2
+ print("nesting coroutines running after recoverable errors")
+ local count = 0
+ local function foo()
+ count = count + 1
+ pcall(1) -- create an error
+ -- running now inside 'precover' ("protected recover")
+ coroutine.wrap(foo)() -- call another coroutine
+ end
+ checkerror("C stack overflow", foo)
+ print("final count: ", count)
+end
+
+
if T then
print("testing stack recovery")
local N = 0 -- trace number of calls
