[PATCH] Allow -fsanitize=thread without -pie

[Jakub Jelinek <jakub@redhat.com>]

On Fri, Nov 21, 2014 at 04:20:44PM +0400, Dmitry Vyukov wrote:
> Yes, I think it's the way to go.
> I've just committed the following revision to clang that removes -pie
> when compiling with tsan:
> http://llvm.org/viewvc/llvm-project?view=revision&revision=222526
> The tests in llvm tree pass with this change.

Ok, here it is.  I think -static still doesn't work, for static linking
symbols might not be interposed as libtsan wants, so I've changed it
to match what we do for -fsanitize=address.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2014-11-26  Jakub Jelinek  <jakub@redhat.com>

	* gcc.c (SANITIZER_SPEC): Don't error on -fsanitize=thread
	without -pie or -shared, error on -fsanitize=thread -static instead.

	* lib/tsan-dg.exp (check_effective_target_fsanitize_thread,
	tsan_init): Don't use -fPIE or -pie.

--- gcc/gcc.c.jj	2014-11-26 11:08:51.000000000 +0100
+++ gcc/gcc.c	2014-11-26 15:59:12.034729813 +0100
@@ -794,7 +794,7 @@ proper position among the other output f
 %{!nostdlib:%{!nodefaultlibs:%{%:sanitize(address):" LIBASAN_SPEC "\
     %{static:%ecannot specify -static with -fsanitize=address}}\
     %{%:sanitize(thread):" LIBTSAN_SPEC "\
-    %{!pie:%{!shared:%e-fsanitize=thread linking must be done with -pie or -shared}}}\
+    %{static:%ecannot specify -static with -fsanitize=thread}}\
     %{%:sanitize(undefined):" LIBUBSAN_SPEC "}\
     %{%:sanitize(leak):" LIBLSAN_SPEC "}}}"
 #endif
--- gcc/testsuite/lib/tsan-dg.exp.jj	2014-10-10 19:42:16.000000000 +0200
+++ gcc/testsuite/lib/tsan-dg.exp	2014-11-26 16:02:21.663347886 +0100
@@ -18,9 +18,9 @@
 # code, 0 otherwise.
 
 proc check_effective_target_fsanitize_thread {} {
-    return [check_no_compiler_messages fanitize_thread executable {
+    return [check_no_compiler_messages fsanitize_thread executable {
 	int main (void) { return 0; }
-    } "-fPIE -pie -fsanitize=thread"]
+    } "-fsanitize=thread"]
 }
 
 #
@@ -93,12 +93,12 @@ proc tsan_init { args } {
     if [info exists ALWAYS_CXXFLAGS] {
 	set tsan_saved_ALWAYS_CXXFLAGS $ALWAYS_CXXFLAGS
 	set ALWAYS_CXXFLAGS [concat "{ldflags=$link_flags}" $ALWAYS_CXXFLAGS]
-	set ALWAYS_CXXFLAGS [concat "{additional_flags=-fPIE -pie -fsanitize=thread -g}" $ALWAYS_CXXFLAGS]
+	set ALWAYS_CXXFLAGS [concat "{additional_flags=-fsanitize=thread -g}" $ALWAYS_CXXFLAGS]
     } else {
 	if [info exists TEST_ALWAYS_FLAGS] {
-	    set TEST_ALWAYS_FLAGS "$link_flags -fPIE -pie -fsanitize=thread -g $TEST_ALWAYS_FLAGS"
+	    set TEST_ALWAYS_FLAGS "$link_flags -fsanitize=thread -g $TEST_ALWAYS_FLAGS"
 	} else {
-	    set TEST_ALWAYS_FLAGS "$link_flags -fPIE -pie -fsanitize=thread -g"
+	    set TEST_ALWAYS_FLAGS "$link_flags -fsanitize=thread -g"
 	}
     }
 
@@ -110,7 +110,7 @@ proc tsan_init { args } {
 	set individual_timeout 20
 	if [check_runtime_nocache tsan_works {
 		int main () { return 0; }
-	    } "-fPIE -pie -fsanitize=thread -g"] {
+	    } "-fsanitize=thread -g"] {
 	    set dg-do-what-default run
 	} else {
 	    set dg-do-what-default compile


	Jakub