[PATCH] Pass -Wl, --no-error-execstack for tests where -Wl, -z, execstack is used [PR32717]

[Sam James]

When GNU Binutils is configured with --enable-error-execstack=yes, a handful
of our tests which rely on -Wl,-z,execstack fail. Pass --Wl,--no-error-execstack
to override the behaviour and get a warning instead.

Bug: https://sourceware.org/PR32717
---
Tested on x86_64-pc-linux-gnu.

 config.make.in |  1 +
 configure      | 35 +++++++++++++++++++++++++++++++++++
 configure.ac   |  4 ++++
 elf/Makefile   |  6 ++++++
 nptl/Makefile  |  3 +++
 5 files changed, 49 insertions(+)

diff --git a/config.make.in b/config.make.in
index 36096881b7..59897eaec2 100644
--- a/config.make.in
+++ b/config.make.in
@@ -53,6 +53,7 @@ c++-bits-std_abs-h = @CXX_BITS_STD_ABS_H@
 enable-werror = @enable_werror@
 
 have-z-execstack = @libc_cv_z_execstack@
+have-no-error-execstack = @libc_cv_no_error_execstack@
 have-protected-data = @libc_cv_protected_data@
 have-insert = @libc_cv_insert@
 have-glob-dat-reloc = @libc_cv_has_glob_dat@
diff --git a/configure b/configure
index eb8abd0054..3d43b7a44a 100755
--- a/configure
+++ b/configure
@@ -659,6 +659,7 @@ libc_cv_has_glob_dat
 libc_cv_fpie
 libc_cv_test_static_pie
 libc_cv_z_execstack
+libc_cv_no_error_execstack
 ASFLAGS_config
 libc_cv_cc_with_libunwind
 libc_cv_insert
@@ -7114,6 +7115,40 @@ if test $libc_cv_as_noexecstack = yes; then
 fi
 
 
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for linker that supports --no-error-execstack" >&5
+printf %s "checking for linker that supports --no-error-execstack... " >&6; }
+libc_linker_feature=no
+cat > conftest.c <<EOF
+int _start (void) { return 42; }
+EOF
+if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
+		  -Wl,-no-error-execstack -nostdlib -nostartfiles
+		  -fPIC -shared -o conftest.so conftest.c
+		  1>&5'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }
+then
+  if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp -Wl,-no-error-execstack -nostdlib \
+      -nostartfiles -fPIC -shared -o conftest.so conftest.c 2>&1 \
+      | grep "warning: --no-error-execstack ignored" > /dev/null 2>&1; then
+    true
+  else
+    libc_linker_feature=yes
+  fi
+fi
+rm -f conftest*
+if test $libc_linker_feature = yes; then
+  libc_cv_no_error_execstack=yes
+else
+  libc_cv_no_error_execstack=no
+fi
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_linker_feature" >&5
+printf "%s\n" "$libc_linker_feature" >&6; }
+
+
 { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for linker that supports -z execstack" >&5
 printf %s "checking for linker that supports -z execstack... " >&6; }
 libc_linker_feature=no
diff --git a/configure.ac b/configure.ac
index 050bfa65e3..f16dbe598f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1318,6 +1318,10 @@ if test $libc_cv_as_noexecstack = yes; then
 fi
 AC_SUBST(ASFLAGS_config)
 
+LIBC_LINKER_FEATURE([--no-error-execstack], [-Wl,-no-error-execstack],
+		    [libc_cv_no_error_execstack=yes], [libc_cv_no_error_execstack=no])
+AC_SUBST(libc_cv_no_error_execstack)
+
 LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
 		    [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
 AC_SUBST(libc_cv_z_execstack)
diff --git a/elf/Makefile b/elf/Makefile
index 1ea0e7037e..41f01b5c89 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -1990,6 +1990,9 @@ $(objpfx)tst-execstack.out: $(objpfx)tst-execstack-mod.so
 CPPFLAGS-tst-execstack.c += -DUSE_PTHREADS=0
 LDFLAGS-tst-execstack = -Wl,-z,noexecstack
 LDFLAGS-tst-execstack-mod.so = -Wl,-z,execstack
+ifeq ($(have-no-error-execstack),yes)
+LDFLAGS-tst-execstack-mod.so += -Wl,--no-error-execstack
+endif
 
 $(objpfx)tst-execstack-needed: $(objpfx)tst-execstack-mod.so
 LDFLAGS-tst-execstack-needed = -Wl,-z,noexecstack
@@ -1999,6 +2002,9 @@ CFLAGS-tst-execstack-prog.c += -Wno-trampolines
 CFLAGS-tst-execstack-mod.c += -Wno-trampolines
 
 LDFLAGS-tst-execstack-prog-static = -Wl,-z,execstack
+ifeq ($(have-no-error-execstack),yes)
+LDFLAGS-tst-execstack-prog-static += -Wl,--no-error-execstack
+endif
 CFLAGS-tst-execstack-prog-static.c += -Wno-trampolines
 
 ifeq (yes,$(build-hardcoded-path-in-tests))
diff --git a/nptl/Makefile b/nptl/Makefile
index 66caa7ab93..f70d1e55bd 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -702,6 +702,9 @@ $(objpfx)tst-execstack-threads.out: $(objpfx)tst-execstack-threads-mod.so
 LDFLAGS-tst-execstack-threads = -Wl,-z,noexecstack
 LDFLAGS-tst-execstack-threads-mod.so = -Wl,-z,execstack
 CFLAGS-tst-execstack-threads-mod.c += -Wno-trampolines
+ifeq ($(have-no-error-execstack),yes)
+LDFLAGS-tst-execstack-threads-mod.so += -Wl,--no-error-execstack
+endif
 
 tst-stackguard1-ARGS = --command "$(host-test-program-cmd) --child"
 tst-stackguard1-static-ARGS = --command "$(objpfx)tst-stackguard1-static --child"
-- 
2.48.1