Backport https://gitlab.haskell.org/ghc/ghc/-/commit/9a28680d2e23e7b2…

…5dd7254a439aea31dfae32d5 to ghc 8.10

overlays/bootstrap.nix

@@ -186,6 +186,7 @@ in {
                 ++ fromUntil "8.10"   "9.2.2"  ./patches/ghc/MR6654-nonmoving-maxmem.patch  # https://gitlab.haskell.org/ghc/ghc/-/merge_requests/6654
                 ++ fromUntil "8.10"   "8.10.8" ./patches/ghc/MR6617-nonmoving-mvar.patch    # https://gitlab.haskell.org/ghc/ghc/-/merge_requests/6617
                 ++ fromUntil "8.10"   "8.10.8" ./patches/ghc/MR6595-nonmoving-mutvar.patch  # https://gitlab.haskell.org/ghc/ghc/-/merge_requests/6595
+                ++ fromUntil "8.10"   "8.11"   ./patches/ghc/ghc-8.10-global-unique-counters-in-rts.patch # backport of https://gitlab.haskell.org/ghc/ghc/-/commit/9a28680d2e23e7b25dd7254a439aea31dfae32d5
                 ;
         in ({
             ghc844 = final.callPackage ../compiler/ghc {

overlays/patches/ghc/ghc-8.10-global-unique-counters-in-rts.patch

@@ -0,0 +1,53 @@
+diff --git a/compiler/cbits/genSym.c b/compiler/cbits/genSym.c
+index ecb318d5a8..8e70db33fc 100644
+--- a/compiler/cbits/genSym.c
++++ b/compiler/cbits/genSym.c
+@@ -1,9 +1,15 @@
+ #include <Rts.h>
+ #include <assert.h>
+ #include "Unique.h"
++#include "ghcversion.h"
+
++// These global variables have been moved into the RTS.  It allows them to be
++// shared with plugins even if two different instances of the GHC library are
++// loaded at the same time (#19940)
++#if !MIN_VERSION_GLASGOW_HASKELL(8,10,0,0)
+ static HsInt GenSymCounter = 0;
+ static HsInt GenSymInc = 1;
++#endif
+
+ #define UNIQUE_BITS (sizeof (HsInt) * 8 - UNIQUE_TAG_BITS)
+ #define UNIQUE_MASK ((1ULL << UNIQUE_BITS) - 1)
+diff --git a/includes/rts/Globals.h b/includes/rts/Globals.h
+index ff36572c56..12db025423 100644
+--- a/includes/rts/Globals.h
++++ b/includes/rts/Globals.h
+@@ -34,3 +34,5 @@ mkStoreAccessorPrototype(LibHSghcInitLinkerDone)
+ mkStoreAccessorPrototype(LibHSghcGlobalDynFlags)
+ mkStoreAccessorPrototype(LibHSghcStaticOptions)
+ mkStoreAccessorPrototype(LibHSghcStaticOptionsReady)
++extern HsInt GenSymCounter;
++extern HsInt GenSymInc;
+diff --git a/rts/Globals.c b/rts/Globals.c
+index c9980d9a3a..56522937ef 100644
+--- a/rts/Globals.c
++++ b/rts/Globals.c
+@@ -111,3 +111,5 @@ mkStoreAccessor(LibHSghcInitLinkerDone)
+ mkStoreAccessor(LibHSghcGlobalDynFlags)
+ mkStoreAccessor(LibHSghcStaticOptions)
+ mkStoreAccessor(LibHSghcStaticOptionsReady)
++HsInt GenSymCounter = 0;
++HsInt GenSymInc = 1;
+diff --git a/rts/RtsSymbols.c b/rts/RtsSymbols.c
+index d5b8cc5fec..7ed561ff3f 100644
+--- a/rts/RtsSymbols.c
++++ b/rts/RtsSymbols.c
+@@ -646,6 +646,8 @@
+       SymI_HasProto(getOrSetLibHSghcPersistentLinkerState)              \
+       SymI_HasProto(getOrSetLibHSghcInitLinkerDone)                     \
+       SymI_HasProto(getOrSetLibHSghcGlobalDynFlags)                     \
++      SymI_HasProto(GenSymCounter)                                      \
++      SymI_HasProto(GenSymInc)                                          \
+       SymI_HasProto(genericRaise)                                       \
+       SymI_HasProto(getProgArgv)                                        \
+       SymI_HasProto(getFullProgArgv)                                    \