FYI: add build_executable_from_specs and prepare_for_testing_full

[Tom Tromey <tromey at redhat dot com>]

I'm checking this in.

This patch adds a couple of new convenience procs to the test suite.
They are like build_executable and prepare_for_testing, but they give
the caller more control over which options are passed to which compile.

A subsequent patch uses this to fix up some bad compiles in gdb.dwarf2;
and my cleanup of gdb.base will also use this.

Tom

2012-07-12  Tom Tromey  <tromey@redhat.com>

	* lib/gdb.exp (build_executable_from_specs): New proc, from
	build_executable.
	(build_executable): Use it.
	(prepare_for_testing_full): New proc.

Index: lib/gdb.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/lib/gdb.exp,v
retrieving revision 1.211
diff -u -r1.211 gdb.exp
--- lib/gdb.exp	10 Jul 2012 14:41:16 -0000	1.211
+++ lib/gdb.exp	12 Jul 2012 15:05:45 -0000
@@ -3734,29 +3734,31 @@
     }
 }
 
-# Build executable named EXECUTABLE, from SOURCES.  If SOURCES are not
-# provided, uses $EXECUTABLE.c.  The TESTNAME paramer is the name of test
-# to pass to untested, if something is wrong.  OPTIONS are passed
-# to gdb_compile directly.
-proc build_executable { testname executable {sources ""} {options {debug}} } {
-
-    global objdir
+# Build executable named EXECUTABLE from specifications that allow
+# different options to be passed to different sub-compilations.
+# TESTNAME is the name of the test; this is passed to 'untested' if
+# something fails.
+# OPTIONS is passed to the final link, using gdb_compile.
+# ARGS is a flat list of source specifications, of the form:
+#    { SOURCE1 OPTIONS1 [ SOURCE2 OPTIONS2 ]... }
+# Each SOURCE is compiled to an object file using its OPTIONS,
+# using gdb_compile.
+# Returns 0 on success, -1 on failure.
+proc build_executable_from_specs {testname executable options args} {
     global subdir
     global srcdir
-    if {[llength $sources]==0} {
-        set sources ${executable}.c
-    }
 
     set binfile [standard_output_file $executable]
 
     set objects {}
-    for {set i 0} "\$i<[llength $sources]" {incr i} {
-        set s [lindex $sources $i]
-        if  { [gdb_compile "${srcdir}/${subdir}/${s}" "${binfile}${i}.o" object $options] != "" } {
+    set i 0
+    foreach {s local_options} $args {
+        if  { [gdb_compile "${srcdir}/${subdir}/${s}" "${binfile}${i}.o" object $local_options] != "" } {
             untested $testname
             return -1
         }
         lappend objects "${binfile}${i}.o"
+	incr i
     }
     
     if  { [gdb_compile $objects "${binfile}" executable $options] != "" } {
@@ -3774,6 +3776,23 @@
     return 0
 }
 
+# Build executable named EXECUTABLE, from SOURCES.  If SOURCES are not
+# provided, uses $EXECUTABLE.c.  The TESTNAME paramer is the name of test
+# to pass to untested, if something is wrong.  OPTIONS are passed
+# to gdb_compile directly.
+proc build_executable { testname executable {sources ""} {options {debug}} } {
+    if {[llength $sources]==0} {
+        set sources ${executable}.c
+    }
+
+    set arglist [list $testname $executable $options]
+    foreach source $sources {
+	lappend arglist $source $options
+    }
+
+    return [eval build_executable_from_specs $arglist]
+}
+
 # Starts fresh GDB binary and loads EXECUTABLE into GDB. EXECUTABLE is
 # the basename of the binary.
 proc clean_restart { executable } {
@@ -3788,6 +3807,25 @@
     gdb_load ${binfile}
 }
 
+# Prepares for testing by calling build_executable_full, then
+# clean_restart.
+# TESTNAME is the name of the test.
+# Each element in ARGS is a list of the form
+#    { EXECUTABLE OPTIONS SOURCE_SPEC... }
+# These are passed to build_executable_from_specs, which see.
+# The last EXECUTABLE is passed to clean_restart.
+# Returns 0 on success, non-zero on failure.
+proc prepare_for_testing_full {testname args} {
+    foreach spec $args {
+	if {[eval build_executable_from_specs [list $testname] $spec] == -1} {
+	    return -1
+	}
+	set executable [lindex $spec 0]
+    }
+    clean_restart $executable
+    return 0
+}
+
 # Prepares for testing, by calling build_executable, and then clean_restart.
 # Please refer to build_executable for parameter description.
 proc prepare_for_testing { testname executable {sources ""} {options {debug}}} {