gnu: gcc@12: Add missing file.

Fixes <https://issues.guix.gnu.org/55616>. Reported by Tim Rakowski <tim.rakowski@gmail.com>. This is a followup to 37e29ccd33. * gnu/packages/patches/gcc-12-strmov-store-file-names.patch: New file. * gnu/local.mk (dist_patch_DATA): Add it.
2022-05-24 21:51:59 +02:00 · 2022-05-24 21:51:59 +02:00 · cdb6b19b5f
parent dc5707f27c
commit cdb6b19b5f
2 changed files with 115 additions and 0 deletions
--- a/gnu/local.mk
+++ b/gnu/local.mk
@ -1136,6 +1136,7 @@ dist_patch_DATA =						\
  %D%/packages/patches/gcc-8-strmov-store-file-names.patch	\
  %D%/packages/patches/gcc-9-asan-fix-limits-include.patch	\
  %D%/packages/patches/gcc-9-strmov-store-file-names.patch	\
+  %D%/packages/patches/gcc-12-strmov-store-file-names.patch	\
  %D%/packages/patches/gcc-10-cross-environment-variables.patch \
  %D%/packages/patches/gcolor3-update-libportal-usage.patch	\
  %D%/packages/patches/gd-fix-tests-on-i686.patch		\
--- a/gnu/packages/patches/gcc-12-strmov-store-file-names.patch
+++ b/gnu/packages/patches/gcc-12-strmov-store-file-names.patch
@ -0,0 +1,114 @@
+Make sure that statements such as:
+
+  strcpy (dst, "/gnu/store/…");
+
+or
+
+  static const char str[] = "/gnu/store/…";
+  …
+  strcpy (dst, str);
+
+do not result in chunked /gnu/store strings that are undetectable by
+Guix's GC and its grafting code.  See <https://bugs.gnu.org/24703>
+and <https://bugs.gnu.org/30395>.
+
+diff --git a/gcc/builtins.cc b/gcc/builtins.cc
+index 5b085e3a1..480bc0b54 100644
+--- a/gcc/builtins.cc
+++ b/gcc/builtins.cc
+@@ -3363,6 +3363,58 @@ expand_builtin_mempcpy (tree exp, rtx target)
+ 				      target, exp, /*retmode=*/ RETURN_END);
+ }
+ 
+extern void debug_tree (tree);
+
+/* Return true if STR contains the string "/gnu/store".  */
+
+bool
+store_reference_p (tree str)
+{
+  if (getenv ("GUIX_GCC_DEBUG") != NULL)
+    debug_tree (str);
+
+  if (TREE_CODE (str) == ADDR_EXPR)
+    str = TREE_OPERAND (str, 0);
+
+  if (TREE_CODE (str) == VAR_DECL
+      && TREE_STATIC (str)
+      && TREE_READONLY (str))
+    {
+      /* STR may be a 'static const' variable whose initial value
+         is a string constant.  See <https://bugs.gnu.org/30395>.  */
+      str = DECL_INITIAL (str);
+      if (str == NULL_TREE)
+        return false;
+    }
+
+  if (TREE_CODE (str) != STRING_CST)
+    return false;
+
+  int len;
+  const char *store;
+
+  store = getenv ("NIX_STORE") ? getenv ("NIX_STORE") : "/gnu/store";
+  len = strlen (store);
+
+  /* Size of the hash part of store file names, including leading slash and
+     trailing hyphen.  */
+  const int hash_len = 34;
+
+  if (TREE_STRING_LENGTH (str) < len + hash_len)
+    return false;
+
+  /* We cannot use 'strstr' because 'TREE_STRING_POINTER' returns a string
+     that is not necessarily NUL-terminated.  */
+
+  for (int i = 0; i < TREE_STRING_LENGTH (str) - (len + hash_len); i++)
+    {
+      if (strncmp (TREE_STRING_POINTER (str) + i, store, len) == 0)
+	return true;
+    }
+
+  return false;
+}
+
+ /* Helper function to do the actual work for expand of memory copy family
+    functions (memcpy, mempcpy, stpcpy).  Expansing should assign LEN bytes
+    of memory from SRC to DEST and assign to TARGET if convenient.  Return
+@@ -3384,6 +3436,13 @@ expand_builtin_memory_copy_args (tree dest, tree src, tree len,
+ 
+   bool is_move_done;
+ 
+  /* Do not emit block moves, which translate to the 'movabs' instruction on
+     x86_64, when SRC refers to store items.  That way, store references
+     remain visible to the Guix GC and grafting code.  See
+     <https://bugs.gnu.org/24703>.  */
+  if (store_reference_p (src))
+    return NULL_RTX;
+
+   /* If DEST is not a pointer type, call the normal function.  */
+   if (dest_align == 0)
+     return NULL_RTX;
+diff --git a/gcc/gimple-fold.cc b/gcc/gimple-fold.cc
+index 863ee3d39..4cc46c265 100644
+--- a/gcc/gimple-fold.cc
+++ b/gcc/gimple-fold.cc
+@@ -856,6 +856,8 @@ var_decl_component_p (tree var)
+ 	      && TREE_CODE (TREE_OPERAND (inner, 0)) == ADDR_EXPR));
+ }
+ 
+extern bool store_reference_p (tree);
+
+ /* Return TRUE if the SIZE argument, representing the size of an
+    object, is in a range of values of which exactly zero is valid.  */
+ 
+@@ -960,6 +962,9 @@ gimple_fold_builtin_memory_op (gimple_stmt_iterator *gsi,
+ 	= build_int_cst (build_pointer_type_for_mode (char_type_node,
+ 						      ptr_mode, true), 0);
+ 
+      if (store_reference_p (src))
+        return false;
+
+       /* If we can perform the copy efficiently with first doing all loads
+          and then all stores inline it that way.  Currently efficiently
+ 	 means that we can load all the memory into a single integer