applgrid: fix build after root update

Assisted-by: Claude:opus-4.7

pkgs/by-name/ap/applgrid/TFileStringLinkDef.h

@@ -0,0 +1,6 @@
+#ifdef __CLING__
+#pragma link off all globals;
+#pragma link off all classes;
+#pragma link off all functions;
+#pragma link C++ class TFileString+;
+#endif

pkgs/by-name/ap/applgrid/TFileVectorLinkDef.h

@@ -0,0 +1,6 @@
+#ifdef __CLING__
+#pragma link off all globals;
+#pragma link off all classes;
+#pragma link off all functions;
+#pragma link C++ class TFileVector+;
+#endif

pkgs/by-name/ap/applgrid/package.nix

@@ -18,7 +18,18 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-h+ZNGj33FIwg4fOCyfGJrUKM2vDDQl76JcLhtboAOtc=";
   };
 
+  patches = [
+    # ROOT 6.40 made rootcling fail when no selection rules are provided
+    # (https://root.cern/doc/v640/release-notes.html#core-libraries). The patch
+    # appends $*LinkDef.h to the dictionary pattern rule so rootcint picks up
+    # the LinkDef.h files we drop into src/ in postPatch.
+    ./rootcling-linkdef.patch
+  ];
+
   postPatch = ''
+    cp ${./TFileStringLinkDef.h} src/TFileStringLinkDef.h
+    cp ${./TFileVectorLinkDef.h} src/TFileVectorLinkDef.h
+
     sed -i appl_grid/serialise_base.h -e '1i#include <cstdint>'
   '';
 

pkgs/by-name/ap/applgrid/rootcling-linkdef.patch

@@ -0,0 +1,11 @@
+--- a/src/Makefile.in
++++ b/src/Makefile.in
+@@ -1027,7 +1027,7 @@
+ 	$(CC) $(AM_CFLAGS) -c $<
+ 
+ @USE_ROOT_TRUE@%Dict.cxx : %.h %.cxx
+-@USE_ROOT_TRUE@	$(CINT) -f $@ -c $< -I.. 
++@USE_ROOT_TRUE@	$(CINT) -f $@ -c $< -I.. $*LinkDef.h
+ 
+ #../appl_grid/$*LinkDef.h
+