[SV 64803] Set origin for unmodified variables after -e

Ensure the origin of all variables inherited from the environment is
"environment override" if -e is given.  Previously only variables
that were set in the makefile had this origin.

PDS: Most of these changes are from Dmitry but I slightly modified
the algorithm: instead of rearranging the way in which MAKEFLAGS is
parsed we reset the env_override value to the default before we
re-parse MAKEFLAGS, then we set the origin of all env vars to the
correct value based on the new setting.

* NEWS: Mention the change for backward-compatibility.
* src/main.c (main): Ensure MAKEFLAGS is always marked special.
(reset_makeflags): Set env_overrides back to default before parsing
MAKEFLAGS.
(decode_switches): Call reset_env_override() to check for changes.
* src/variable.h (reset_env_override): Declare a new function.
* src/variable.c (reset_env_override): Go through all env variables
and ensure the origin is correct based on env_overrides.
(set_env_override): Helper function for the hash.
* tests/scripts/functions/foreach: Fix tests.
* tests/scripts/functions/let: Ditto.
* tests/scripts/functions/origin: Ditto.
* tests/scripts/options/dash-e: Add tests.

src/main.c

@@ -1445,6 +1445,7 @@ main (int argc, char **argv, char **envp)
 #endif
 
   /* Initialize the special variables.  */
+  define_variable_cname ("MAKEFLAGS", "", o_default, 0)->special = 1;
   define_variable_cname (".VARIABLES", "", o_default, 0)->special = 1;
   /* define_variable_cname (".TARGETS", "", o_default, 0)->special = 1; */
   define_variable_cname (".RECIPEPREFIX", "", o_default, 0)->special = 1;
@@ -3090,6 +3091,8 @@ handle_non_switch_argument (const char *arg, enum variable_origin origin)
 void
 reset_makeflags (enum variable_origin origin)
 {
+  /* Reset to default values.  */
+  env_overrides = 0;
   decode_env_switches (STRING_SIZE_TUPLE(MAKEFLAGS_NAME), origin);
   construct_include_path (include_dirs ? include_dirs->list : NULL);
   disable_builtins ();
@@ -3363,6 +3366,9 @@ decode_switches (int argc, const char **argv, enum variable_origin origin)
 
   /* Perform any special switch handling.  */
   run_silent = silent_flag;
+
+  /* Check variable priorities.  */
+  reset_env_override ();
 }
 
 /* Decode switches from environment variable ENVAR (which is LEN chars long).
@@ -3453,8 +3459,8 @@ quote_for_env (char *out, const char *in)
 }
 
 /* Disable builtin variables and rules, if -R or -r is specified.
- * This function is called at parse time whenever MAKEFLAGS is modified and
- * also when the parsing phase is over.  */
+   This function is called at parse time whenever MAKEFLAGS is modified and
+   also when the parsing phase is over.  */
 
 static
 void disable_builtins ()
@@ -3837,7 +3843,7 @@ die (int status)
         verify_file_data_base ();
 
       /* Unload plugins before jobserver integrity check in case a plugin
-       * participates in jobserver.  */
+         participates in jobserver.  */
       unload_all ();
 
       clean_jobserver (status);

src/variable.c

@@ -564,9 +564,7 @@ lookup_variable (const char *name, size_t length)
                     *nptr++ = '$';
                   }
                 else
-                  {
-                    *nptr++ = *sptr;
-                  }
+                  *nptr++ = *sptr;
                 sptr++;
               }
 
@@ -704,12 +702,10 @@ initialize_file_variables (struct file *file, int reading)
                   v->flavor = f_simple;
                 }
               else
-                {
-                  v = do_variable_definition (
-                    &p->variable.fileinfo, p->variable.name, p->variable.value,
-                    p->variable.origin, p->variable.flavor,
-                    p->variable.conditional, s_pattern);
-                }
+                v = do_variable_definition (
+                  &p->variable.fileinfo, p->variable.name, p->variable.value,
+                  p->variable.origin, p->variable.flavor,
+                  p->variable.conditional, s_pattern);
 
               /* Also mark it as a per-target and copy export status. */
               v->per_target = p->variable.per_target;
@@ -1911,6 +1907,23 @@ warn_undefined (const char *name, size_t len)
                     (int)len, name));
     }
 }
+
+static void
+set_env_override (const void *item, void *arg UNUSED)
+{
+  struct variable *v = (struct variable *)item;
+  enum variable_origin old = env_overrides ? o_env : o_env_override;
+  enum variable_origin new = env_overrides ? o_env_override : o_env;
+
+  if (v->origin == old)
+    v->origin = new;
+}
+
+void
+reset_env_override ()
+{
+  hash_map_arg (&global_variable_set.table, set_env_override, NULL);
+}
 
 /* Print information for variable V, prefixing it with PREFIX.  */
 
@@ -1985,7 +1998,6 @@ print_variable (const void *item, void *arg)
     }
 }
 
-
 static void
 print_auto_variable (const void *item, void *arg)
 {
@@ -1995,7 +2007,6 @@ print_auto_variable (const void *item, void *arg)
     print_variable (item, arg);
 }
 
-
 static void
 print_noauto_variable (const void *item, void *arg)
 {
@@ -2005,7 +2016,6 @@ print_noauto_variable (const void *item, void *arg)
     print_variable (item, arg);
 }
 
-
 /* Print all the variables in SET.  PREFIX is printed before
    the actual variable definitions (everything else is comments).  */
 

src/variable.h

@@ -205,6 +205,7 @@ struct variable *define_variable_in_set (const char *name, size_t length,
                                          struct variable_set *set,
                                          const floc *flocp);
 void warn_undefined (const char* name, size_t length);
+void reset_env_override (void);
 
 /* Define a variable in the current variable set.  */