diff --git a/src/libraries/project/project.ml b/src/libraries/project/project.ml
index ec66fdebc1096de932680f2b40704a1d81132a43..efd97ce0af5374b322b4a4e9c1e68c559a0d3f64 100644
--- a/src/libraries/project/project.ml
+++ b/src/libraries/project/project.ml
@@ -151,7 +151,7 @@ module States_operations = struct
   let unserialize ?selection dst loaded_states =
     let pp_err fmt n msg_sing msg_plural =
       if n > 0 then begin
-        warning ~once:true
+        warning ~once:true ~wkey
           fmt
           n
           (if n = 1 then "" else "s")
diff --git a/src/libraries/project/project_skeleton.ml b/src/libraries/project/project_skeleton.ml
index 117344bf22051f2fe0d6fb22b36533b7df1449c0..3251b34074361e39db00858c0df59dfa91997f01 100644
--- a/src/libraries/project/project_skeleton.ml
+++ b/src/libraries/project/project_skeleton.ml
@@ -27,6 +27,7 @@
 module Output = struct
   include Cmdline.Kernel_log
   let dkey = register_category "project"
+  let wkey = register_warn_category "project"
 end
 
 (* ************************************************************************** *)
diff --git a/src/libraries/project/project_skeleton.mli b/src/libraries/project/project_skeleton.mli
index c6c7e4b8969b8f41ade21c8286f5ea263ac1fb27..7db8448429ccf425cd7171c5b381214df5232955 100644
--- a/src/libraries/project/project_skeleton.mli
+++ b/src/libraries/project/project_skeleton.mli
@@ -31,6 +31,7 @@
 module Output : sig
   include Log.Messages
   val dkey: category
+  val wkey: warn_category
   (** @since Fluorine-20130401 *)
 end
 
diff --git a/tests/misc/oracle/audit-out.json b/tests/misc/oracle/audit-out.json
index 0307758ad6290a6a5ea7f4fc5d4105fd2618319b..f078d477d54e3ec8c44cda9d46117251acba0e6e 100644
--- a/tests/misc/oracle/audit-out.json
+++ b/tests/misc/oracle/audit-out.json
@@ -63,8 +63,8 @@
         "parser:conditional-feature", "parser:unnamed-typedef",
         "parser:unsupported", "parser:unsupported:attributes",
         "parser:unsupported:pragma", "plugin-not-loaded", "pp",
-        "pp:compilation-db", "pp:line-directive", "too-large-array",
-        "typing", "typing:implicit-conv-void-ptr",
+        "pp:compilation-db", "pp:line-directive", "project",
+        "too-large-array", "typing", "typing:implicit-conv-void-ptr",
         "typing:implicit-function-declaration",
         "typing:incompatible-pointer-types",
         "typing:incompatible-types-call", "typing:inconsistent-specifier",
diff --git a/tests/misc/oracle/my_visitor.1.res.oracle b/tests/misc/oracle/my_visitor.1.res.oracle
index d7de4e33c03d33fa164d9ed0f242f9ad5ded2499..ebb3e44d45d8398e6a652866704d54f92f3d7415 100644
--- a/tests/misc/oracle/my_visitor.1.res.oracle
+++ b/tests/misc/oracle/my_visitor.1.res.oracle
@@ -1,9 +1,11 @@
 [kernel] Warning: emitter emitter1: correctness parameter -s does not exist anymore. Ignored.
 [kernel] Warning: emitter emitter2: correctness parameter -s2 does not exist anymore. Ignored.
-[kernel] Warning: 13 states in saved file ignored. They are invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  13 states in saved file ignored. They are invalid in this Frama-C configuration.
 [kernel] Warning: emitter emitter1: correctness parameter -s does not exist anymore. Ignored.
 [kernel] Warning: emitter emitter2: correctness parameter -s2 does not exist anymore. Ignored.
-[kernel] Warning: 13 states in saved file ignored. They are invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  13 states in saved file ignored. They are invalid in this Frama-C configuration.
 /* Generated by Frama-C */
 int f(void)
 {
diff --git a/tests/misc/oracle/orphan_emitter.res.oracle b/tests/misc/oracle/orphan_emitter.res.oracle
index 54742d6322b5c706a0bf20f509252bf510f016ba..4ec5b3c8d753b3bfaf487b5f46c85b3f6e420345 100644
--- a/tests/misc/oracle/orphan_emitter.res.oracle
+++ b/tests/misc/oracle/orphan_emitter.res.oracle
@@ -1,2 +1,3 @@
 [kernel] Warning: emitter emitter1: correctness parameter -orphan does not exist anymore. Ignored.
-[kernel] Warning: 9 states in saved file ignored. They are invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  9 states in saved file ignored. They are invalid in this Frama-C configuration.
diff --git a/tests/saveload/oracle/basic.0.res.oracle b/tests/saveload/oracle/basic.0.res.oracle
index 0fe986b70a1ed12971d4f09a2d440bb47f152d5f..fc63130180936baf28b86f4b8956cb66a15f394d 100644
--- a/tests/saveload/oracle/basic.0.res.oracle
+++ b/tests/saveload/oracle/basic.0.res.oracle
@@ -1 +1,2 @@
-[kernel] Warning: 1 state in saved file ignored. It is invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  1 state in saved file ignored. It is invalid in this Frama-C configuration.
diff --git a/tests/saveload/oracle/basic.4.res.oracle b/tests/saveload/oracle/basic.4.res.oracle
index eeed93b93d1467d26a2d89b1bca0736fb1c0c510..49d86b7d41ef9b53f191ddd967c07109da8b2d8f 100644
--- a/tests/saveload/oracle/basic.4.res.oracle
+++ b/tests/saveload/oracle/basic.4.res.oracle
@@ -1 +1,2 @@
-[kernel] Warning: 9 states in saved file ignored. They are invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  9 states in saved file ignored. They are invalid in this Frama-C configuration.
diff --git a/tests/saveload/oracle/deps.1.res.oracle b/tests/saveload/oracle/deps.1.res.oracle
index 86d7a2aa4ea6852ffe77c514b82169f16a040c6d..1d5bc198f26f613424e35c20bd11b9cecc4b27a3 100644
--- a/tests/saveload/oracle/deps.1.res.oracle
+++ b/tests/saveload/oracle/deps.1.res.oracle
@@ -1 +1,2 @@
-[kernel] Warning: 2 states in saved file ignored. They are invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  2 states in saved file ignored. They are invalid in this Frama-C configuration.
diff --git a/tests/saveload/oracle/deps.2.res.oracle b/tests/saveload/oracle/deps.2.res.oracle
index 86d7a2aa4ea6852ffe77c514b82169f16a040c6d..1d5bc198f26f613424e35c20bd11b9cecc4b27a3 100644
--- a/tests/saveload/oracle/deps.2.res.oracle
+++ b/tests/saveload/oracle/deps.2.res.oracle
@@ -1 +1,2 @@
-[kernel] Warning: 2 states in saved file ignored. They are invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  2 states in saved file ignored. They are invalid in this Frama-C configuration.
diff --git a/tests/saveload/oracle/deps.4.res.oracle b/tests/saveload/oracle/deps.4.res.oracle
index 0ace314a020f9c99ef7b61fbdaab5789416dcfd4..7aaa68b760b8b8be1cec097c1018429aaa294858 100644
--- a/tests/saveload/oracle/deps.4.res.oracle
+++ b/tests/saveload/oracle/deps.4.res.oracle
@@ -1,2 +1,4 @@
-[kernel] Warning: 1 state in saved file ignored. It is invalid in this Frama-C configuration.
-[kernel] Warning: 1 state in memory reset to their default value. It is inconsistent in this Frama_C configuration.
+[kernel:project] Warning: 
+  1 state in saved file ignored. It is invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  1 state in memory reset to their default value. It is inconsistent in this Frama_C configuration.
diff --git a/tests/saveload/oracle/segfault_datatypes.res.oracle b/tests/saveload/oracle/segfault_datatypes.res.oracle
index 0fe986b70a1ed12971d4f09a2d440bb47f152d5f..fc63130180936baf28b86f4b8956cb66a15f394d 100644
--- a/tests/saveload/oracle/segfault_datatypes.res.oracle
+++ b/tests/saveload/oracle/segfault_datatypes.res.oracle
@@ -1 +1,2 @@
-[kernel] Warning: 1 state in saved file ignored. It is invalid in this Frama-C configuration.
+[kernel:project] Warning: 
+  1 state in saved file ignored. It is invalid in this Frama-C configuration.