re PR go/78978 (runtime/pprof FAILs on Solaris 2/x86)

	PR go/78978
    libgo: build with -Wa,-nH if possible on Solaris
    
    By default the Solaris assembler records the required hardware
    capability in the object file.  This means that the AES hashing code
    breaks on systems that do not support AES, even though the code uses a
    runtime check to only actually invoke the AES instructions on systems
    that support it.  An earlier fix for the problem only fixed the shared
    library, not the static libgo.a.  Fix the problem for real by using an
    assembler option to not record the hardware capability.
    
    For GCC PR 78978.
    
    Patch by Rainer Orth.
    
    Reviewed-on: https://go-review.googlesource.com/34910

From-SVN: r244165

gcc/go/gofrontend/MERGE

-dfe446c5a54ca0febabb81b542cc4e634c6f5c30
+eef0fb3b092dc22d9830cac15a536760da5d033a
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

libgo/Makefile.am

@@ -42,14 +42,12 @@ ACLOCAL_AMFLAGS = -I ./config -I ../config
 
 AM_CFLAGS = -fexceptions -fnon-call-exceptions -fplan9-extensions \
 	$(SPLIT_STACK) $(WARN_CFLAGS) \
-	$(STRINGOPS_FLAG) $(OSCFLAGS) \
+	$(STRINGOPS_FLAG) $(HWCAP_CFLAGS) $(OSCFLAGS) \
 	-I $(srcdir)/../libgcc -I $(srcdir)/../libbacktrace \
 	-I $(MULTIBUILDTOP)../../gcc/include
 
-AM_LDFLAGS = $(HWCAP_LDFLAGS)
-
 if USING_SPLIT_STACK
-AM_LDFLAGS += -XCClinker $(SPLIT_STACK)
+AM_LDFLAGS = -XCClinker $(SPLIT_STACK)
 endif
 
 # Multilib support.

libgo/Makefile.in

@@ -62,9 +62,8 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 target_triplet = @target@
-@USING_SPLIT_STACK_TRUE@am__append_1 = -XCClinker $(SPLIT_STACK)
-@GOC_IS_LLGO_TRUE@am__append_2 = libgo-llgo.la libgobegin-llgo.a
-@GOC_IS_LLGO_FALSE@am__append_3 = libgo.la libgobegin.a
+@GOC_IS_LLGO_TRUE@am__append_1 = libgo-llgo.la libgobegin-llgo.a
+@GOC_IS_LLGO_FALSE@am__append_2 = libgo.la libgobegin.a
 subdir = .
 DIST_COMMON = README $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
 	$(top_srcdir)/configure $(am__configure_deps) \
@@ -321,7 +320,7 @@ GO_SPLIT_STACK = @GO_SPLIT_STACK@
 GO_SYSCALL_OS_ARCH_FILE = @GO_SYSCALL_OS_ARCH_FILE@
 GO_SYSCALL_OS_FILE = @GO_SYSCALL_OS_FILE@
 GREP = @GREP@
-HWCAP_LDFLAGS = @HWCAP_LDFLAGS@
+HWCAP_CFLAGS = @HWCAP_CFLAGS@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
@@ -459,11 +458,11 @@ AM_CPPFLAGS = -I $(srcdir)/runtime $(LIBFFIINCS) $(PTHREAD_CFLAGS)
 ACLOCAL_AMFLAGS = -I ./config -I ../config
 AM_CFLAGS = -fexceptions -fnon-call-exceptions -fplan9-extensions \
 	$(SPLIT_STACK) $(WARN_CFLAGS) \
-	$(STRINGOPS_FLAG) $(OSCFLAGS) \
+	$(STRINGOPS_FLAG) $(HWCAP_CFLAGS) $(OSCFLAGS) \
 	-I $(srcdir)/../libgcc -I $(srcdir)/../libbacktrace \
 	-I $(MULTIBUILDTOP)../../gcc/include
 
-AM_LDFLAGS = $(HWCAP_LDFLAGS) $(am__append_1)
+@USING_SPLIT_STACK_TRUE@AM_LDFLAGS = -XCClinker $(SPLIT_STACK)
 
 # Multilib support.
 MAKEOVERRIDES = 
@@ -1120,7 +1119,7 @@ CHECK_DEPS = $(toolexeclibgo_DATA) $(toolexeclibgoarchive_DATA) \
 	$(toolexeclibgorpc_DATA) $(toolexeclibgoruntime_DATA) \
 	$(toolexeclibgosync_DATA) $(toolexeclibgotesting_DATA) \
 	$(toolexeclibgotext_DATA) $(toolexeclibgotexttemplate_DATA) \
-	$(toolexeclibgounicode_DATA) $(am__append_2) $(am__append_3)
+	$(toolexeclibgounicode_DATA) $(am__append_1) $(am__append_2)
 
 # Pass -ffp-contract=off, or 386-specific options, when building the
 # math package.  MATH_FLAG is defined in configure.ac.

libgo/configure

@@ -624,9 +624,7 @@ GO_SPLIT_STACK
 USING_SPLIT_STACK_FALSE
 USING_SPLIT_STACK_TRUE
 SPLIT_STACK
-HAVE_HWCAP_FALSE
-HAVE_HWCAP_TRUE
-HWCAP_LDFLAGS
+HWCAP_CFLAGS
 OSCFLAGS
 GO_SYSCALL_OS_ARCH_FILE
 GO_SYSCALL_OS_FILE
@@ -11106,7 +11104,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11109 "configure"
+#line 11107 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11212,7 +11210,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11215 "configure"
+#line 11213 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -13912,15 +13910,18 @@ esac
 
 
 
-  test -z "$HWCAP_LDFLAGS" && HWCAP_LDFLAGS=''
+  test -z "$HWCAP_CFLAGS" && HWCAP_CFLAGS=''
 
+  # Restrict the test to Solaris, other assemblers (e.g. AIX as) have -nH
+  # with a different meaning.
+  case ${target_os} in
+    solaris2*)
+      ac_save_CFLAGS="$CFLAGS"
+      CFLAGS="$CFLAGS -Wa,-nH"
 
-  ac_save_LDFLAGS="$LDFLAGS"
-  LDFLAGS="$LFLAGS -mclear-hwcap"
-
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -mclear-hwcap" >&5
-$as_echo_n "checking for -mclear-hwcap... " >&6; }
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for as that supports -Wa,-nH" >&5
+$as_echo_n "checking for as that supports -Wa,-nH... " >&6; }
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
@@ -13931,31 +13932,23 @@ return 0;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  ac_hwcap_ldflags=yes
+if ac_fn_c_try_compile "$LINENO"; then :
+  ac_hwcap_flags=yes
 else
-  ac_hwcap_ldflags=no
+  ac_hwcap_flags=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-  if test "$ac_hwcap_ldflags" = "yes"; then
-    HWCAP_LDFLAGS="-mclear-hwcap $HWCAP_LDFLAGS"
-  fi
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_hwcap_ldflags" >&5
-$as_echo "$ac_hwcap_ldflags" >&6; }
-
-  LDFLAGS="$ac_save_LDFLAGS"
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+      if test "$ac_hwcap_flags" = "yes"; then
+	HWCAP_CFLAGS="-Wa,-nH $HWCAP_CFLAGS"
+      fi
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_hwcap_flags" >&5
+$as_echo "$ac_hwcap_flags" >&6; }
 
+      CFLAGS="$ac_save_CFLAGS"
+      ;;
+  esac
 
 
-   if test $ac_hwcap_ldflags != no; then
-  HAVE_HWCAP_TRUE=
-  HAVE_HWCAP_FALSE='#'
-else
-  HAVE_HWCAP_TRUE='#'
-  HAVE_HWCAP_FALSE=
-fi
-
 
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -fsplit-stack is supported" >&5
@@ -15764,10 +15757,6 @@ if test -z "${LIBGO_IS_BSD_TRUE}" && test -z "${LIBGO_IS_BSD_FALSE}"; then
   as_fn_error "conditional \"LIBGO_IS_BSD\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
-if test -z "${HAVE_HWCAP_TRUE}" && test -z "${HAVE_HWCAP_FALSE}"; then
-  as_fn_error "conditional \"HAVE_HWCAP\" was never defined.
-Usually this means the macro was only invoked conditionally." "$LINENO" 5
-fi
 if test -z "${USING_SPLIT_STACK_TRUE}" && test -z "${USING_SPLIT_STACK_FALSE}"; then
   as_fn_error "conditional \"USING_SPLIT_STACK\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5

libgo/configure.ac

@@ -421,8 +421,8 @@ case "$target" in
 esac
 AC_SUBST(OSCFLAGS)
 
-dnl Check linker hardware capability support.
-GCC_CHECK_LINKER_HWCAP
+dnl Check if assembler supports disabling hardware capability support.
+GCC_CHECK_ASSEMBLER_HWCAP
 
 dnl Use -fsplit-stack when compiling C code if available.
 AC_CACHE_CHECK([whether -fsplit-stack is supported],

libgo/testsuite/Makefile.in

@@ -124,7 +124,7 @@ GO_SPLIT_STACK = @GO_SPLIT_STACK@
 GO_SYSCALL_OS_ARCH_FILE = @GO_SYSCALL_OS_ARCH_FILE@
 GO_SYSCALL_OS_FILE = @GO_SYSCALL_OS_FILE@
 GREP = @GREP@
-HWCAP_LDFLAGS = @HWCAP_LDFLAGS@
+HWCAP_CFLAGS = @HWCAP_CFLAGS@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@