[SV 62324] Simplify set_file_variables by passing in the stem

Previously we always used the file->stem value as our stem in
set_file_variables(); when that wasn't correct we had to temporarily
set that value while the function was called, then reset it afterward.
This led to issues (for example when we assumed the stem was a cached
string but it wasn't).

Avoid this by passing in the stem as an argument so that different
values can be provided.

Add tests to verify this.

* src/commands.c (set_file_variables): Take second parameter stem to
relieve the callers of set_file_variables() from setting/restoring
file->stem.
* src/commands.h (set_file_variables): Ditto.
(execute_file_commands): Pass file->stem to set_file_variables().
* src/file.c (expand_deps): Pass d->stem to set_file_variables() and
remove set and restore of file->stem.
* src/implicit.c (pattern_search): Pass stem to set_file_variables()
and remove set and restore of file->stem.
* tests/scripts/features/se_explicit: Add new tests.
* tests/scripts/features/se_implicit: Ditto.
* tests/scripts/features/se_statpat: Ditto.
* tests/scripts/variables/automatic: Ditto.

src/commands.c

@@ -58,10 +58,13 @@ dep_hash_cmp (const void *x, const void *y)
   return strcmp (dep_name (dx), dep_name (dy));
 }
 
-/* Set FILE's automatic variables up.  */
+/* Set FILE's automatic variables up.
+ * Use STEM to set $*.
+ * If STEM is 0, then set FILE->STEM and $* to the target name with any
+ * suffix in the .SUFFIXES list stripped off.  */
 
 void
-set_file_variables (struct file *file)
+set_file_variables (struct file *file, const char *stem)
 {
   struct dep *d;
   const char *at, *percent, *star, *less;
@@ -95,7 +98,7 @@ set_file_variables (struct file *file)
     }
 
   /* $* is the stem from an implicit or static pattern rule.  */
-  if (file->stem == 0)
+  if (stem == 0)
     {
       /* In Unix make, $* is set to the target name with
          any suffix in the .SUFFIXES list stripped off for
@@ -121,14 +124,14 @@ set_file_variables (struct file *file)
           size_t slen = strlen (dep_name (d));
           if (len > slen && strneq (dep_name (d), name + (len - slen), slen))
             {
-              file->stem = strcache_add_len (name, len - slen);
+              file->stem = stem = strcache_add_len (name, len - slen);
               break;
             }
         }
       if (d == 0)
-        file->stem = "";
+        file->stem = stem = "";
     }
-  star = file->stem;
+  star = stem;
 
   /* $< is the first not order-only dependency.  */
   less = "";
@@ -464,7 +467,7 @@ execute_file_commands (struct file *file)
 
   initialize_file_variables (file, 0);
 
-  set_file_variables (file);
+  set_file_variables (file, file->stem);
 
   /* If this is a loaded dynamic object, unload it before remaking.
      Some systems don't support overwriting a loaded object.  */

src/commands.h

@@ -42,4 +42,4 @@ void execute_file_commands (struct file *file);
 void print_commands (const struct commands *cmds);
 void delete_child_targets (struct child *child);
 void chop_commands (struct commands *cmds);
-void set_file_variables (struct file *file);
+void set_file_variables (struct file *file, const char *stem);

src/file.c

@@ -571,7 +571,6 @@ expand_deps (struct file *f)
 {
   struct dep *d;
   struct dep **dp;
-  const char *file_stem = f->stem;
   const char *fstem;
   int initialized = 0;
 
@@ -646,19 +645,13 @@ expand_deps (struct file *f)
           initialized = 1;
         }
 
-      if (d->stem != 0)
-        f->stem = d->stem;
-
-      set_file_variables (f);
+      set_file_variables (f, d->stem ? d->stem : f->stem);
 
       p = variable_expand_for_file (d->name, f);
 
       /* Free the un-expanded name.  */
       free ((char*)d->name);
 
-      if (d->stem != 0)
-        f->stem = file_stem;
-
       /* Parse the prerequisites and enter them into the file database.  */
       new = split_prereqs (p);
 

src/implicit.c

@@ -521,10 +521,6 @@ pattern_search (struct file *file, int archive,
           if (rule->deps == 0)
             break;
 
-          /* Temporary assign STEM to file->stem (needed to set file
-             variables below).   */
-          file->stem = stem_str;
-
           /* Mark this rule as in use so a recursive pattern_search won't try
              to use it.  */
           rule->in_use = 1;
@@ -666,14 +662,14 @@ pattern_search (struct file *file, int archive,
                   if (!file_vars_initialized)
                     {
                       initialize_file_variables (file, 0);
-                      set_file_variables (file);
+                      set_file_variables (file, stem_str);
                       file_vars_initialized = 1;
                     }
                   /* Update the stem value in $* for this rule.  */
                   else if (!file_variables_set)
                     {
                       define_variable_for_file (
-                        "*", 1, file->stem, o_automatic, 0, file);
+                        "*", 1, stem_str, o_automatic, 0, file);
                       file_variables_set = 1;
                     }
 
@@ -913,10 +909,6 @@ pattern_search (struct file *file, int archive,
                 break;
             }
 
-          /* Reset the stem in FILE. */
-
-          file->stem = 0;
-
           /* This rule is no longer 'in use' for recursive searches.  */
           rule->in_use = 0;
 

tests/scripts/features/se_explicit

@@ -291,5 +291,12 @@ all: 2.x 1.x
 #MAKE#: Nothing to be done for 'all'.\n");
 
 
+# sv 62324.
+# Integrity self check.
+run_make_test(q!
+.SECONDEXPANSION:
+all: bye.x
+bye.x: $$(firstword bye.1;
+!, '', "#MAKEFILE#:4: *** unterminated call to function 'firstword': missing ')'.  Stop.", 512);
 
 1;

tests/scripts/features/se_implicit

@@ -434,6 +434,13 @@ all: 2.x
 "@=2.x,<=,^=,+=,|=,?=,*=2
 #MAKE#: Nothing to be done for 'all'.\n");
 
+# sv 62324.
+# Integrity self check.
+run_make_test(q!
+.SECONDEXPANSION:
+all: bye.x
+%.x: $$(firstword %.1;
+!, '', "#MAKE#: *** unterminated call to function 'firstword': missing ')'.  Stop.", 512);
 
 # This tells the test driver that the perl test script executed properly.
 1;

tests/scripts/features/se_statpat

@@ -102,6 +102,13 @@ oo$ba.1
 oo$ba
 ');
 
+# sv 62324.
+# Integrity self check.
+run_make_test(q!
+.SECONDEXPANSION:
+all: bye.x
+bye.x: %.x: $$(firstword %.1;
+!, '', "#MAKEFILE#:4: *** unterminated call to function 'firstword': missing ')'.  Stop.", 512);
 
 # This tells the test driver that the perl test script executed properly.
 1;

tests/scripts/variables/automatic

@@ -91,6 +91,30 @@ mbr.src: ; @:',
               '',
               'mbr');
 
+# Same as above with second expansion.
+#
+run_make_test('
+.SECONDEXPANSION:
+.SUFFIXES: .b .src
+
+p:=mbr.src
+mbr.b: $$p
+	@echo $*
+
+mbr.src: ; @:',
+              '',
+              'mbr');
+
+# Test that $* is set to empty string for unknown suffixes.
+
+run_make_test('
+mbr.b: mbr.src
+	@echo star=$*
+
+mbr.src: ; @:',
+              '',
+              "star=\n");
+
 # TEST #3 -- test for Savannah bug #8154
 # Make sure that nonexistent prerequisites are listed in $?, since they are
 # considered reasons for the target to be rebuilt.