[Patch, testsuite] clear wrap_compile_flags before setting it

[Christophe Lyon]

Hi,

In testsuite/lib/wrapper.exp's ${tool}_maybe_build_wrapper, we call
set_currtarget_info wrap_compile_flags
to override wrap_compile_flags with additional flags when compiling testglue.c.

However, dejagnu's set_currtarget_info {entry value} will write into
value only if it's not already defined.

This caused me problems since I had defined wrap_compile_flags much
earlier in my main .exp file: -w was not added, causing compilation of
testglue.c to fail under RHEL5.

The attach patch unsets wrap_compile_flags before calling set_currtarget_info.

OK for trunk?

Thanks,
Christophe

2014-10-17  Christophe Lyon  <christophe.l...@linaro.org>

       * lib/wrapper.exp ({tool}_maybe_build_wrapper): Clear
       wrap_compile_flags before setting it.

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 29ed3e6..faadd79 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-10-17  Christophe Lyon  <christophe.l...@linaro.org>
+
+       * lib/wrapper.exp ({tool}_maybe_build_wrapper): Clear
+       wrap_compile_flags before setting it.
+
 2014-10-17  Marek Polacek  <pola...@redhat.com>
 
        PR c/63543
diff --git a/gcc/testsuite/lib/wrapper.exp b/gcc/testsuite/lib/wrapper.exp
index 1291c11..6880172 100644
--- a/gcc/testsuite/lib/wrapper.exp
+++ b/gcc/testsuite/lib/wrapper.exp
@@ -34,9 +34,11 @@ proc ${tool}_maybe_build_wrapper { filename args } {
        # became true for dejagnu-1.4.4.  The set of warnings and code
        # that gcc objects on may change, so just make sure -w is always
        # passed to turn off all warnings.
+       unset_currtarget_info wrap_compile_flags
        set_currtarget_info wrap_compile_flags \
            "$saved_wrap_compile_flags -w $flags"
        set result [build_wrapper $filename]
+       unset_currtarget_info wrap_compile_flags
        set_currtarget_info wrap_compile_flags "$saved_wrap_compile_flags"
        if { $result != "" } {
            set gluefile [lindex $result 0]