diff --git a/tests/compliance/check-json.i b/tests/compliance/check-json.i
index e539fed3e6158f6f6fb5c289b3118f7a5ba67eae..cce5ee0c72fd8bfff0f6616323d476924a45e012 100644
--- a/tests/compliance/check-json.i
+++ b/tests/compliance/check-json.i
@@ -1,11 +1,11 @@
 /*run.config
  MACRO: SHARE @FRAMAC_SHARE@/compliance
  NOFRAMAC:
-  EXECNOW: LOG json_@PTEST_NAME@_1.txt python3 -m json.tool < @SHARE@/c11_functions.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_1.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_2.txt python3 -m json.tool < @SHARE@/glibc_functions.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_2.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_3.txt python3 -m json.tool < @SHARE@/nonstandard_identifiers.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_3.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_4.txt python3 -m json.tool < @SHARE@/posix_identifiers.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_4.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_5.txt python3 -m json.tool < @SHARE@/compiler_builtins.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_5.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_6.txt python3 -m json.tool < @SHARE@/gcc_builtins.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_6.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_1.txt python3 -m json.tool < @SHARE@/c11_functions.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_1.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_2.txt python3 -m json.tool < @SHARE@/glibc_functions.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_2.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_3.txt python3 -m json.tool < @SHARE@/nonstandard_identifiers.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_3.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_4.txt python3 -m json.tool < @SHARE@/posix_identifiers.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_4.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_5.txt python3 -m json.tool < @SHARE@/compiler_builtins.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_5.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_6.txt python3 -m json.tool < @SHARE@/gcc_builtins.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_6.txt 2> @DEV_NULL@
   EXECNOW: LOG json_@PTEST_NAME@_7.txt python3 @PTEST_DIR@/sanity-checks.py @SHARE@ > @PTEST_RESULT@/json_@PTEST_NAME@_7.txt 2> @DEV_NULL@
 */
diff --git a/tests/compliance/oracle/json_check-json_1.txt b/tests/compliance/oracle/json_check-json_1.txt
index 1b5870264ab3d7511f6c0ec3cce36b2ddf76554c..53e785991f5381a46f4610e816316649ccae7e5e 100644
--- a/tests/compliance/oracle/json_check-json_1.txt
+++ b/tests/compliance/oracle/json_check-json_1.txt
@@ -1,2 +1 @@
-{
     "description": "C11 reserved function and macro identifiers",
diff --git a/tests/compliance/oracle/json_check-json_2.txt b/tests/compliance/oracle/json_check-json_2.txt
index a7490e8d444cf0359541826585e85c435704ea3e..24ce34e11953f9c80a6861f91fcfc97fe6f70171 100644
--- a/tests/compliance/oracle/json_check-json_2.txt
+++ b/tests/compliance/oracle/json_check-json_2.txt
@@ -1,2 +1 @@
-{
     "description": "Function and macro identifiers defined in the GNU C Library",
diff --git a/tests/compliance/oracle/json_check-json_3.txt b/tests/compliance/oracle/json_check-json_3.txt
index 0b2f8f38fd6866c709dd788271b9c62fe2a52bf0..567fa7bd16e3060df956746d155eb99beecf0acf 100644
--- a/tests/compliance/oracle/json_check-json_3.txt
+++ b/tests/compliance/oracle/json_check-json_3.txt
@@ -1,2 +1 @@
-{
     "description": "Non-ISO C, Non-POSIX identifiers known to the Frama-C standard library",
diff --git a/tests/compliance/oracle/json_check-json_4.txt b/tests/compliance/oracle/json_check-json_4.txt
index cdf3ccde431a21b0e3e97353e314452444a135a1..ba1f81a5fad309e92a7b2db78855d59bd595be79 100644
--- a/tests/compliance/oracle/json_check-json_4.txt
+++ b/tests/compliance/oracle/json_check-json_4.txt
@@ -1,2 +1 @@
-{
     "description": "POSIX.1-2008 reserved function identifiers (plus a few legacy POSIX identifiers)",
diff --git a/tests/compliance/oracle/json_check-json_5.txt b/tests/compliance/oracle/json_check-json_5.txt
index 8dc6444a05eaf72e22c8a75faba583aafcf91210..41629175862962f64941c7ec80ef2948a41e695a 100644
--- a/tests/compliance/oracle/json_check-json_5.txt
+++ b/tests/compliance/oracle/json_check-json_5.txt
@@ -1,2 +1 @@
-{
     "description": "Compiler builtins supported by Frama-C (for GCC builtins, see gcc_builtins.json)",
diff --git a/tests/compliance/oracle/json_check-json_6.txt b/tests/compliance/oracle/json_check-json_6.txt
index ece8bd177c4c175d66c5ea4e1b5cc18255337a7a..6984653217284e726bb24afefc98bf10d49420a2 100644
--- a/tests/compliance/oracle/json_check-json_6.txt
+++ b/tests/compliance/oracle/json_check-json_6.txt
@@ -1,2 +1 @@
-{
     "description": "GCC builtins supported by Frama-C",