Non-portable echo usage in sysdeps/unix/make-syscalls.sh

[Jakub Bogusz]

Hello,

Some paths of make-syscalls.sh script use echo in a way specific to
bash or echo from GNU coreutils, expecting not to interpret escape
sequences by default.
It's contrary to what POSIX specs say and the way that echo from
some other shells (like ksh or dash) works (escape sequences are
always interpreted or are interpreted by default).

The attached patch is a try to fix the problem by avoiding non
portable cases.


-- 
Jakub Bogusz    http://qboosh.pl/
-------------- next part --------------
--- glibc-2.20/sysdeps/unix/make-syscalls.sh.orig	2014-09-07 10:09:09.000000000 +0200
+++ glibc-2.20/sysdeps/unix/make-syscalls.sh	2014-12-21 17:54:48.973388216 +0100
@@ -276,28 +276,33 @@
     vdso_symbol="${vdso_syscall%@*}"
     vdso_symver="${vdso_syscall#*@}"
     vdso_symver=`echo "$vdso_symver" | sed 's/\./_/g'`
-    echo "\
+    cat <<EOF
+
 \$(foreach p,\$(sysd-rules-targets),\$(objpfx)\$(patsubst %,\$p,$file).os): \\
-		\$(..)sysdeps/unix/make-syscalls.sh\
+		\$(..)sysdeps/unix/make-syscalls.sh
 	\$(make-target-directory)
 	(echo '#include <dl-vdso.h>'; \\
-	 echo 'extern void *${strong}_ifunc (void) __asm (\"${strong}\");'; \\
+	 echo 'extern void *${strong}_ifunc (void) __asm ("${strong}");'; \\
 	 echo 'void *'; \\
 	 echo '${strong}_ifunc (void)'; \\
 	 echo '{'; \\
 	 echo '  PREPARE_VERSION_KNOWN (symver, ${vdso_symver});'; \\
-	 echo '  return _dl_vdso_vsym (\"${vdso_symbol}\", &symver);'; \\
+	 echo '  return _dl_vdso_vsym ("${vdso_symbol}", &symver);'; \\
 	 echo '}'; \\
-	 echo 'asm (\".type ${strong}, %gnu_indirect_function\");'; \\"
+	 echo 'asm (".type ${strong}, %gnu_indirect_function");'; \\
+EOF
     # This is doing "libc_hidden_def (${strong})", but the compiler
     # doesn't know that we've defined ${strong} in the same file, so
     # we can't do it the normal way.
-    echo "\
-	 echo 'asm (\".globl __GI_${strong}\\n\"'; \\
-	 echo '     \"__GI_${strong} = ${strong}\");'; \\"
+    cat <<EOF
+	 echo 'asm (".globl __GI_${strong}");'; \\
+	 echo 'asm ("__GI_${strong} = ${strong}");'; \\
+EOF
     emit_weak_aliases
-    echo '	) | $(compile-stdin.c) '"\
-\$(foreach p,\$(patsubst %$file,%,\$(basename \$(@F))),\$(\$(p)CPPFLAGS))"
+    cat <<EOF
+	) | \$(compile-stdin.c) \
+\$(foreach p,\$(patsubst %$file,%,\$(basename \$(@F))),\$(\$(p)CPPFLAGS))
+EOF
   fi
 
   if test $shared_only = t; then