Darwin: Check as for .build_version support and use it if available.

This adds support for the minimum OS version data in assembler files.
At present, we have no mechanism to detect the SDK version in use, and
so that is omitted from build_versions.

We follow the implementation in clang, '.build_version' is only emitted
(where supported) for target macOS versions >= 10.14.  For earlier macOS
we fall back to using a '.macosx_version_min' directive.  This latter is
also emitted when the assembler supports it, but not build_version.

gcc/ChangeLog:

	* config.in: Regenerate.
	* config/darwin.cc (darwin_file_start): Add assembler directives
	for the target OS version, where these are supported by the
	assembler.
	(darwin_override_options): Check for building >= macOS 10.14.
	* configure: Regenerate.
	* configure.ac: Check for assembler support of .build_version
	directives.

Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
(cherry picked from commit a4184c8a65a00eaf8a8d7f92fb8ad2f8621b39e2)

diff --git a/gcc/config.in b/gcc/config.in
index 83c98ae14574d446d3f9d32aeb21c642c70580b9..5281a12a707c918ce4955c7b60e8ef91de57f0c8 100644 (file)
--- a/gcc/config.in
+++ b/gcc/config.in
@@ -610,6 +610,12 @@
 #endif
 
 
+/* Define if your macOS assembler supports .build_version directives */
+#ifndef USED_FOR_TARGET
+#undef HAVE_AS_MACOS_BUILD_VERSION
+#endif
+
+
 /* Define if the assembler understands -march=rv*_zifencei. */
 #ifndef USED_FOR_TARGET
 #undef HAVE_AS_MARCH_ZIFENCEI
@@ -635,8 +641,7 @@
 #endif
 
 
-/* Define if your Mac OS X assembler supports the -mmacos-version-min option.
-   */
+/* Define if your macOS assembler supports the -mmacos-version-min option. */
 #ifndef USED_FOR_TARGET
 #undef HAVE_AS_MMACOSX_VERSION_MIN_OPTION
 #endif

diff --git a/gcc/config/darwin.cc b/gcc/config/darwin.cc
index 5e1b8ccd4eb4dc5f0228ffaf4b5e78bc8e9512f8..d719ef29cd68fa6691730c9c08cf0622c9a36239 100644 (file)
--- a/gcc/config/darwin.cc
+++ b/gcc/config/darwin.cc
@@ -3021,7 +3021,35 @@ darwin_asm_output_dwarf_offset (FILE *file, int size, const char * lab,
 void
 darwin_file_start (void)
 {
-  /* Nothing to do.  */
+#ifdef HAVE_AS_MMACOSX_VERSION_MIN_OPTION
+  /* This should not happen with a well-formed command line, but the user could
+     invoke cc1* directly without it.  */
+  if (!darwin_macosx_version_min)
+    return;
+  /* This assumes that the version passed has been validated in the driver.  */
+  unsigned maj, min, tiny;
+  int count = sscanf (darwin_macosx_version_min, "%u.%u.%u", &maj, &min, &tiny);
+  if (count < 0)
+    return;
+  if (count < 3)
+    tiny = 0;
+  if (count < 2)
+    min = 0;
+  const char *directive;
+#ifdef HAVE_AS_MACOS_BUILD_VERSION
+  /* We only handle macos, so far.  */
+  if (generating_for_darwin_version >= 18)
+    directive = "build_version macos, ";
+  else
+#endif
+    directive = "macosx_version_min ";
+  if (count > 2 && tiny != 0)
+    fprintf (asm_out_file, "\t.%s %u, %u, %u\n", directive, maj, min, tiny);
+  else if (count > 1)
+    fprintf (asm_out_file, "\t.%s %u, %u\n", directive, maj, min);
+  else
+     fprintf (asm_out_file, "\t.%s %u, 0\n", directive, maj);
+#endif
 }
 
 /* Called for the TARGET_ASM_FILE_END hook.
@@ -3243,7 +3271,9 @@ darwin_override_options (void)
   /* Keep track of which (major) version we're generating code for.  */
   if (darwin_macosx_version_min)
     {
-      if (strverscmp (darwin_macosx_version_min, "10.7") >= 0)
+      if (strverscmp (darwin_macosx_version_min, "10.14") >= 0)
+       generating_for_darwin_version = 18;
+      else if (strverscmp (darwin_macosx_version_min, "10.7") >= 0)
        generating_for_darwin_version = 11;
       else if (strverscmp (darwin_macosx_version_min, "10.6") >= 0)
        generating_for_darwin_version = 10;

diff --git a/gcc/configure b/gcc/configure
index bb675fdd46152d6e228fa7132affc97abf333c80..ade0af23e8cc155376a2b3d2748a9354b36ae539 100755 (executable)
--- a/gcc/configure
+++ b/gcc/configure
@@ -26266,6 +26266,39 @@ $as_echo "#define HAVE_AS_MMACOSX_VERSION_MIN_OPTION 1" >>confdefs.h
 
 fi
 
+    if test x$gcc_cv_as_mmacosx_version_min = "xyes"; then
+       { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for .build_version" >&5
+$as_echo_n "checking assembler for .build_version... " >&6; }
+if ${gcc_cv_as_darwin_build_version+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  gcc_cv_as_darwin_build_version=no
+  if test x$gcc_cv_as != x; then
+    $as_echo ' .build_version macos, 10, 14 sdk_version 10, 14' > conftest.s
+    if { ac_try='$gcc_cv_as $gcc_cv_as_flags -mmacosx-version-min=10.14 -o conftest.o conftest.s >&5'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }
+    then
+       gcc_cv_as_darwin_build_version=yes
+    else
+      echo "configure: failed program was" >&5
+      cat conftest.s >&5
+    fi
+    rm -f conftest.o conftest.s
+  fi
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_as_darwin_build_version" >&5
+$as_echo "$gcc_cv_as_darwin_build_version" >&6; }
+if test $gcc_cv_as_darwin_build_version = yes; then
+
+$as_echo "#define HAVE_AS_MACOS_BUILD_VERSION 1" >>confdefs.h
+
+fi
+
+    fi
     ;;
 esac
 

diff --git a/gcc/configure.ac b/gcc/configure.ac
index 70a51919e24f4461d70941e29113cd3b0a6e9ca7..bf8ff4d639062092a2f1b450d625c25fe86b6ded 100644 (file)
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -4348,7 +4348,15 @@ case "$target_os" in
       gcc_cv_as_mmacosx_version_min,
       [-mmacosx-version-min=10.1], [.text],,
       [AC_DEFINE(HAVE_AS_MMACOSX_VERSION_MIN_OPTION, 1,
-       [Define if your Mac OS X assembler supports the -mmacos-version-min option.])])
+       [Define if your macOS assembler supports the -mmacos-version-min option.])])
+    if test x$gcc_cv_as_mmacosx_version_min = "xyes"; then
+       gcc_GAS_CHECK_FEATURE([.build_version],
+           gcc_cv_as_darwin_build_version,
+           [-mmacosx-version-min=10.14],
+           [ .build_version macos, 10, 14 sdk_version 10, 14],,
+      [AC_DEFINE(HAVE_AS_MACOS_BUILD_VERSION, 1,
+       [Define if your macOS assembler supports .build_version directives])])
+    fi
     ;;
 esac