automation/eclair: add deviations of MISRA C Rule 5.5

MISRA C Rule 5.5 states that "Identifiers shall be distinct from macro
names".

Update ECLAIR configuration to deviate:
- macros expanding to their own name;
- clashes between macros and non-callable entities;
- clashes related to the selection of specific implementations of string
  handling functions.

Signed-off-by: Federico Serafini <federico.serafini@bugseng.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>

automation/eclair_analysis/ECLAIR/deviations.ecl

@@ -90,6 +90,22 @@ conform to the directive."
 -config=MC3R1.R5.3,reports+={safe, "any_area(any_loc(any_exp(macro(^read_debugreg$))&&any_exp(macro(^write_debugreg$))))"}
 -doc_end
 
+-doc_begin="Macros expanding to their own identifier (e.g., \"#define x x\") are deliberate."
+-config=MC3R1.R5.5,reports+={deliberate, "all_area(macro(same_id_body())||!macro(!same_id_body()))"}
+-doc_end
+
+-doc_begin="There is no clash between function like macros and not callable objects."
+-config=MC3R1.R5.5,reports+={deliberate, "all_area(macro(function_like())||decl(any()))&&all_area(macro(any())||!decl(kind(function))&&!decl(__function_pointer_decls))"}
+-doc_end
+
+-doc_begin="Clashes between function names and macros are deliberate for string handling functions since some architectures may want to use their own arch-specific implementation."
+-config=MC3R1.R5.5,reports+={deliberate, "all_area(all_loc(file(^xen/arch/x86/string\\.c|xen/include/xen/string\\.h|xen/lib/.*$)))"}
+-doc_end
+
+-doc_begin="In libelf, clashes between macros and function names are deliberate and needed to prevent the use of undecorated versions of memcpy, memset and memmove."
+-config=MC3R1.R5.5,reports+={deliberate, "any_area(decl(kind(function))||any_loc(macro(name(memcpy||memset||memmove))))&&any_area(any_loc(file(^xen/common/libelf/libelf-private\\.h$)))"}
+-doc_end
+
 -doc_begin="The type \"ret_t\" is deliberately defined multiple times,
 depending on the guest."
 -config=MC3R1.R5.6,reports+={deliberate,"any_area(any_loc(text(^.*ret_t.*$)))"}

docs/misra/deviations.rst

@@ -98,6 +98,27 @@ Deviations related to MISRA C:2012 Rules:
          - __emulate_2op and __emulate_2op_nobyte
          - read_debugreg and write_debugreg
 
+   * - R5.5
+     - Macros expanding to their own name are allowed.
+     - Tagged as `deliberate` for ECLAIR.
+
+   * - R5.5
+     - Clashes between names of function-like macros and identifiers of
+       non-callable entities are allowed.
+     - Tagged as `deliberate` for ECLAIR.
+
+   * - R5.5
+     - Clashes between function names and macros are deliberate for string
+       handling functions since some architectures may want to use their own
+       arch-specific implementation.
+     - Tagged as `deliberate` for ECLAIR.
+
+   * - R5.5
+     - In libelf, clashes between macros and function names are deliberate and
+       needed to prevent the use of undecorated versions of memcpy, memset and
+       memmove.
+     - Tagged as `deliberate` for ECLAIR.
+
    * - R5.6
      - The type ret_t is deliberately defined multiple times depending on the
        type of guest to service.