Backported from mainline

	2019-10-31  Jakub Jelinek  <jakub@redhat.com>

	PR preprocessor/92296
	* internal.h (struct def_pragma_macro): Add is_builtin bitfield.
	(_cpp_restore_special_builtin): Declare.
	* init.c (_cpp_restore_special_builtin): New function.
	* directives.c (do_pragma_push_macro): For NT_BUILTIN_MACRO
	set is_builtin and don't try to grab definition.
	(cpp_pop_definition): Use _cpp_restore_special_builtin to restore
	builtin macros.

	* c-c++-common/cpp/pr92296-1.c: New test.
	* c-c++-common/cpp/pr92296-2.c: New test.


git-svn-id: https://gcc.gnu.org/svn/gcc/branches/gcc-9-branch@277987 138bc75d-0d04-0410-961f-82ee72b054a4

7 files changed, 153 insertions, 0 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index cd15635f2a7..161f91acf46 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -3,6 +3,10 @@
 	Backported from mainline
 	2019-10-31  Jakub Jelinek  <jakub@redhat.com>
 
+	PR preprocessor/92296
+	* c-c++-common/cpp/pr92296-1.c: New test.
+	* c-c++-common/cpp/pr92296-2.c: New test.
+
 	PR middle-end/92231
 	* gcc.c-torture/compile/pr92231.c: New test.
 
diff --git a/gcc/testsuite/c-c++-common/cpp/pr92296-1.c b/gcc/testsuite/c-c++-common/cpp/pr92296-1.c
new file mode 100644
index 00000000000..4bd69c8be87
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/cpp/pr92296-1.c
@@ -0,0 +1,32 @@
+/* PR preprocessor/92296 */
+/* { dg-do preprocess } */
+
+#pragma push_macro("__TIMESTAMP__")
+#pragma pop_macro("__TIMESTAMP__")
+
+#pragma push_macro("__TIME__")
+#pragma pop_macro("__TIME__")
+
+#pragma push_macro("__DATE__")
+#pragma pop_macro("__DATE__")
+
+#pragma push_macro("__FILE__")
+#pragma pop_macro("__FILE__")
+
+#pragma push_macro("__BASE_FILE__")
+#pragma pop_macro("__BASE_FILE__")
+
+#pragma push_macro("__LINE__")
+#pragma pop_macro("__LINE__")
+
+#pragma push_macro("__INCLUDE_LEVEL__")
+#pragma pop_macro("__INCLUDE_LEVEL__")
+
+#pragma push_macro("__COUNTER__")
+#pragma pop_macro("__COUNTER__")
+
+#pragma push_macro("__has_attribute")
+#pragma pop_macro("__has_attribute")
+
+#pragma push_macro("__has_cpp_attribute")
+#pragma pop_macro("__has_cpp_attribute")
diff --git a/gcc/testsuite/c-c++-common/cpp/pr92296-2.c b/gcc/testsuite/c-c++-common/cpp/pr92296-2.c
new file mode 100644
index 00000000000..15362a4bdc3
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/cpp/pr92296-2.c
@@ -0,0 +1,73 @@
+/* PR preprocessor/92296 */
+/* { dg-do preprocess } */
+/* { dg-options "-Wno-builtin-macro-redefined" } */
+
+#pragma push_macro("__TIMESTAMP__")
+#undef __TIMESTAMP__
+#define __TIMESTAMP__ "Thu Oct 31 12:00:00 2019"
+timestamp1 = __TIMESTAMP__
+#pragma pop_macro("__TIMESTAMP__")
+timestamp2 = __TIMESTAMP__
+
+#pragma push_macro("__TIME__")
+#undef __TIME__
+#define __TIME__ "12:00:00"
+time1 = __TIME__
+#pragma pop_macro("__TIME__")
+time2 = __TIME__
+
+#pragma push_macro("__DATE__")
+#undef __DATE__
+#define __DATE__ "Oct 31 2019"
+date1 = __DATE__
+#pragma pop_macro("__DATE__")
+date2 = __DATE__
+
+#pragma push_macro("__FILE__")
+#undef __FILE__
+#define __FILE__ "pr92296-3.c"
+file1 = __FILE__	/* { dg-final { scan-file pr92296-2.i "file1 = \"pr92296-3.c\"" } } */
+#pragma pop_macro("__FILE__")
+file2 = __FILE__	/* { dg-final { scan-file-not pr92296-2.i "file2 = \"pr92296-3.c\"" } } */
+
+#pragma push_macro("__BASE_FILE__")
+#undef __BASE_FILE__
+#define __BASE_FILE__ "pr92296-4.c"
+filebase1 = __BASE_FILE__	/* { dg-final { scan-file pr92296-2.i "filebase1 = \"pr92296-4.c\"" } } */
+#pragma pop_macro("__BASE_FILE__")
+filebase2 = __BASE_FILE__	/* { dg-final { scan-file-not pr92296-2.i "filebase2 = \"pr92296-4.c\"" } } */
+
+#pragma push_macro("__LINE__")
+#undef __LINE__		/* { dg-warning "undefining" } */
+#define __LINE__ 142
+line1 = __LINE__	/* { dg-final { scan-file pr92296-2.i "line1 = 142" } } */
+#pragma pop_macro("__LINE__")
+line2 = __LINE__	/* { dg-final { scan-file pr92296-2.i "line2 = 45" } } */
+
+#pragma push_macro("__INCLUDE_LEVEL__")
+#undef __INCLUDE_LEVEL__	/* { dg-warning "undefining" } */
+#define __INCLUDE_LEVEL__ 42
+includelevel1 = __INCLUDE_LEVEL__	/* { dg-final { scan-file pr92296-2.i "includelevel1 = 42" } } */
+#pragma pop_macro("__INCLUDE_LEVEL__")
+includelevel2 = __INCLUDE_LEVEL__	/* { dg-final { scan-file pr92296-2.i "includelevel2 = 0" } } */
+
+#pragma push_macro("__COUNTER__")
+#undef __COUNTER__	/* { dg-warning "undefining" } */
+#define __COUNTER__ 172
+counter1 = __COUNTER__	/* { dg-final { scan-file pr92296-2.i "counter1 = 172" } } */
+#pragma pop_macro("__COUNTER__")
+counter2 = __COUNTER__	/* { dg-final { scan-file-not pr92296-2.i "counter2 = 172" } } */
+
+#pragma push_macro("__has_attribute")
+#undef __has_attribute	/* { dg-warning "undefining" } */
+#define __has_attribute(x) 0
+hasattr1 = __has_attribute(noreturn)	/* { dg-final { scan-file pr92296-2.i "hasattr1 = 0" } } */
+#pragma pop_macro("__has_attribute")
+hasattr2 = __has_attribute(noreturn)	/* { dg-final { scan-file-not pr92296-2.i "hasattr2 = 0" } } */
+
+#pragma push_macro("__has_cpp_attribute")
+#undef __has_cpp_attribute	/* { dg-warning "undefining" } */
+#define __has_cpp_attribute(x) 0
+hasattrcpp1 = __has_cpp_attribute(noreturn)	/* { dg-final { scan-file pr92296-2.i "hasattrcpp1 = 0" } } */
+#pragma pop_macro("__has_cpp_attribute")
+hasattrcpp2 = __has_cpp_attribute(noreturn)	/* { dg-final { scan-file-not pr92296-2.i "hasattrcpp2 = 0" } } */
diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog
index 99e2386de14..68c9237cf03 100644
--- a/libcpp/ChangeLog
+++ b/libcpp/ChangeLog
@@ -1,3 +1,17 @@
+2019-11-08  Jakub Jelinek  <jakub@redhat.com>
+
+	Backported from mainline
+	2019-10-31  Jakub Jelinek  <jakub@redhat.com>
+
+	PR preprocessor/92296
+	* internal.h (struct def_pragma_macro): Add is_builtin bitfield.
+	(_cpp_restore_special_builtin): Declare.
+	* init.c (_cpp_restore_special_builtin): New function.
+	* directives.c (do_pragma_push_macro): For NT_BUILTIN_MACRO
+	set is_builtin and don't try to grab definition.
+	(cpp_pop_definition): Use _cpp_restore_special_builtin to restore
+	builtin macros.
+
 2019-08-12  Release Manager
 
 	* GCC 9.2.0 released.
diff --git a/libcpp/directives.c b/libcpp/directives.c
index 1ada834da17..d78e4b7fc19 100644
--- a/libcpp/directives.c
+++ b/libcpp/directives.c
@@ -1564,6 +1564,8 @@ do_pragma_push_macro (cpp_reader *pfile)
   node = _cpp_lex_identifier (pfile, c->name);
   if (node->type == NT_VOID)
     c->is_undef = 1;
+  else if (node->type == NT_BUILTIN_MACRO)
+    c->is_builtin = 1;
   else
     {
       defn = cpp_macro_definition (pfile, node);
@@ -2452,6 +2454,11 @@ cpp_pop_definition (cpp_reader *pfile, struct def_pragma_macro *c)
 
   if (c->is_undef)
     return;
+  if (c->is_builtin)
+    {
+      _cpp_restore_special_builtin (pfile, c);
+      return;
+    }
 
   {
     size_t namelen;
diff --git a/libcpp/init.c b/libcpp/init.c
index 60d25889857..7f2f976037a 100644
--- a/libcpp/init.c
+++ b/libcpp/init.c
@@ -489,6 +489,25 @@ cpp_init_special_builtins (cpp_reader *pfile)
     }
 }
 
+/* Restore macro C to builtin macro definition.  */
+
+void
+_cpp_restore_special_builtin (cpp_reader *pfile, struct def_pragma_macro *c)
+{
+  size_t len = strlen (c->name);
+
+  for (const struct builtin_macro *b = builtin_array;
+       b < builtin_array + ARRAY_SIZE (builtin_array); b++)
+    if (b->len == len && memcmp (c->name, b->name, len + 1) == 0)
+      {
+	cpp_hashnode *hp = cpp_lookup (pfile, b->name, b->len);
+	hp->type = NT_BUILTIN_MACRO;
+	if (b->always_warn_if_redefined)
+	  hp->flags |= NODE_WARN;
+	hp->value.builtin = (enum cpp_builtin_type) b->value;
+      }
+}
+
 /* Read the builtins table above and enter them, and language-specific
    macros, into the hash table.  HOSTED is true if this is a hosted
    environment.  */
diff --git a/libcpp/internal.h b/libcpp/internal.h
index 77a2a3becb3..496c9d63236 100644
--- a/libcpp/internal.h
+++ b/libcpp/internal.h
@@ -380,6 +380,8 @@ struct def_pragma_macro {
 
   /* Mark if we save an undefined macro.  */
   unsigned int is_undef : 1;
+  /* Nonzero if it was a builtin macro.  */
+  unsigned int is_builtin : 1;
 };
 
 /* A cpp_reader encapsulates the "state" of a pre-processor run.
@@ -712,6 +714,8 @@ extern void *_cpp_commit_buff (cpp_reader *pfile, size_t size);
 /* In init.c.  */
 extern void _cpp_maybe_push_include_file (cpp_reader *);
 extern const char *cpp_named_operator2name (enum cpp_ttype type);
+extern void _cpp_restore_special_builtin (cpp_reader *pfile,
+					  struct def_pragma_macro *);
 
 /* In directives.c */
 extern int _cpp_test_assertion (cpp_reader *, unsigned int *);