Fix gdb.compile/compile.exp shlib regression

Commit 6e774b13c3b8 (Make ftrace tests work with remote targets) made
a few gdb.compile/compile.exp tests disappear:

 -PASS: gdb.compile/compile.exp: call shared library function
 -PASS: gdb.compile/compile.exp: expect 1
 -PASS: gdb.compile/compile.exp: modify shared library variable
 -PASS: gdb.compile/compile.exp: expect 15

This is because the test uses ldflags instead of using the shlib
option, so it misses linking with -rpath, resulting in:

 (gdb) run
 Starting program: .../compile/compile-shlib
 .../compile/compile-shlib: error while loading shared libraries: compile-shlib.so: cannot open shared object file: No such file or directory
 [Inferior 1 (process 18014) exited with code 0177]

We were missing a gdb_load_shlibs call, which is needed for remote
testing.

gdb/testsuite/ChangeLog:
2015-04-07  Pedro Alves  <palves@redhat.com>

	* gdb.compile/compile.exp: Use gdb_compile with "shlib=" option
	instead of build_executable.  Use gdb_load_shlibs.

1 files changed, 7 insertions, 3 deletions

diff --git a/gdb/testsuite/gdb.compile/compile.exp b/gdb/testsuite/gdb.compile/compile.exp
index 07a7568..a8bfc24 100644
--- a/gdb/testsuite/gdb.compile/compile.exp
+++ b/gdb/testsuite/gdb.compile/compile.exp
@@ -362,13 +362,17 @@ if {[skip_shlib_tests]} {
 }
 
 set libbin [standard_output_file ${testfile}-shlib.so]
+set binfile [standard_output_file ${testfile}-shlib]
+
 if { [gdb_compile_shlib ${srcdir}/${subdir}/${srcfile2} $libbin {debug}] != ""
-     || [build_executable $testfile ${testfile}-shlib $srcfile \
-	     [list debug ldflags=$libbin]] == -1 } {
+     || [gdb_compile ${srcdir}/${subdir}/${srcfile} $binfile executable \
+	     [list debug shlib=$libbin]] == -1 } {
     return -1
 }
 
-clean_restart ${testfile}-shlib
+clean_restart $binfile
+gdb_load_shlibs $libbin
+
 if ![runto_main] {
     return -1
 }