lua54/upstream-bugs.patch

From 47cffdc723c2e0c6dfaf62b7775ca1c1d338c0a4 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Wed, 7 Apr 2021 14:59:26 -0300
Subject: [PATCH] Bug: tbc variables in "for" loops don't avoid tail calls

---
 lparser.c         | 21 +++++++++++++++------
 testes/locals.lua | 23 +++++++++++++++++++++++
 2 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/lparser.c b/lparser.c
index 284ef1f0c..df9473c27 100644
--- a/src/lparser.c
+++ b/src/lparser.c
@@ -416,6 +416,17 @@ static void markupval (FuncState *fs, int level) {
 }
 
 
+/*
+** Mark that current block has a to-be-closed variable.
+*/
+static void marktobeclosed (FuncState *fs) {
+  BlockCnt *bl = fs->bl;
+  bl->upval = 1;
+  bl->insidetbc = 1;
+  fs->needclose = 1;
+}
+
+
 /*
 ** Find a variable with the given name 'n'. If it is an upvalue, add
 ** this upvalue into all intermediate functions. If it is a global, set
@@ -1599,7 +1610,7 @@ static void forlist (LexState *ls, TString *indexname) {
   line = ls->linenumber;
   adjust_assign(ls, 4, explist(ls, &e), &e);
   adjustlocalvars(ls, 4);  /* control variables */
-  markupval(fs, fs->nactvar);  /* last control var. must be closed */
+  marktobeclosed(fs);  /* last control var. must be closed */
   luaK_checkstack(fs, 3);  /* extra space to call generator */
   forbody(ls, base, line, nvars - 4, 1);
 }
@@ -1703,11 +1714,9 @@ static int getlocalattribute (LexState *ls) {
 }
 
 
-static void checktoclose (LexState *ls, int level) {
+static void checktoclose (FuncState *fs, int level) {
   if (level != -1) {  /* is there a to-be-closed variable? */
-    FuncState *fs = ls->fs;
-    markupval(fs, level + 1);
-    fs->bl->insidetbc = 1;  /* in the scope of a to-be-closed variable */
+    marktobeclosed(fs);
     luaK_codeABC(fs, OP_TBC, reglevel(fs, level), 0, 0);
   }
 }
@@ -1751,7 +1760,7 @@ static void localstat (LexState *ls) {
     adjust_assign(ls, nvars, nexps, &e);
     adjustlocalvars(ls, nvars);
   }
-  checktoclose(ls, toclose);
+  checktoclose(fs, toclose);
 }
 
 
From d205f3a4847bc8b835fda91f51ba1cf45b796baf Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Sat, 10 Apr 2021 10:19:21 -0300
Subject: [PATCH] Bug: Lua source should not use C99 comments ("//")

---
 lvm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lvm.c b/lvm.c
index c9729bcca..16e01d683 100644
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -1156,8 +1156,10 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
     Instruction i;  /* instruction being executed */
     StkId ra;  /* instruction's A register */
     vmfetch();
-// low-level line tracing for debugging Lua
-// printf("line: %d\n", luaG_getfuncline(cl->p, pcRel(pc, cl->p)));
+    #if 0
+      /* low-level line tracing for debugging Lua */
+      printf("line: %d\n", luaG_getfuncline(cl->p, pcRel(pc, cl->p)));
+    #endif
     lua_assert(base == ci->func + 1);
     lua_assert(base <= L->top && L->top < L->stack_last);
     /* invalidate top for instructions not expecting it */
From 681297187ec45268e872b26753c441586c12bdd8 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Fri, 16 Apr 2021 15:41:44 -0300
Subject: [PATCH] Bug: yielding in '__close' mess up number of returns

Yielding in a __close metamethod called when returning vararg results
changes the top and so messes up the number of returned values.
---
 lstate.h          |  2 +-
 lvm.c             | 12 +++++++++-
 testes/locals.lua | 59 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+), 2 deletions(-)

diff --git a/lstate.h b/lstate.h
index c1283bb6b..44cf939cb 100644
--- a/src/lstate.h
+++ b/src/lstate.h
@@ -165,7 +165,7 @@ typedef struct stringtable {
 ** - field 'nyield' is used only while a function is "doing" an
 ** yield (from the yield until the next resume);
 ** - field 'nres' is used only while closing tbc variables when
-** returning from a C function;
+** returning from a function;
 ** - field 'transferinfo' is used only during call/returnhooks,
 ** before the function starts or after it ends.
 */
diff --git a/lvm.c b/lvm.c
index 16e01d683..e4b1903e7 100644
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -847,10 +847,19 @@ void luaV_finishOp (lua_State *L) {
       luaV_concat(L, total);  /* concat them (may yield again) */
       break;
     }
-    case OP_CLOSE:  case OP_RETURN: {  /* yielded closing variables */
+    case OP_CLOSE: {  /* yielded closing variables */
       ci->u.l.savedpc--;  /* repeat instruction to close other vars. */
       break;
     }
+    case OP_RETURN: {  /* yielded closing variables */
+      StkId ra = base + GETARG_A(inst);
+      /* adjust top to signal correct number of returns, in case the
+         return is "up to top" ('isIT') */
+      L->top = ra + ci->u2.nres;
+      /* repeat instruction to close other vars. and complete the return */
+      ci->u.l.savedpc--;
+      break;
+    }
     default: {
       /* only these other opcodes can yield */
       lua_assert(op == OP_TFORCALL || op == OP_CALL ||
@@ -1672,6 +1681,7 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
           n = cast_int(L->top - ra);  /* get what is available */
         savepc(ci);
         if (TESTARG_k(i)) {  /* may there be open upvalues? */
+          ci->u2.nres = n;  /* save number of returns */
           if (L->top < ci->top)
             L->top = ci->top;
           luaF_close(L, base, CLOSEKTOP, 1);