test.html: Mention PCH_CXXFLAGS.

* docs/html/test.html: Mention PCH_CXXFLAGS.
	* testsuite/lib/libstdc++.exp: Set PCH_CXXFLAGS by probing for an
	available stcd++.h PCH.
	* testsuite/libstdc++-dg/normal.exp: Use PCH_CXXFLAGS.

From-SVN: r100264

libstdc++-v3/ChangeLog

@@ -1,3 +1,10 @@
+2005-05-27  Mark Mitchell  <mark@codesourcery.com>
+
+	* docs/html/test.html: Mention PCH_CXXFLAGS.
+	* testsuite/lib/libstdc++.exp: Set PCH_CXXFLAGS by probing for an
+	available stcd++.h PCH.
+	* testsuite/libstdc++-dg/normal.exp: Use PCH_CXXFLAGS.
+
 2005-05-27  Theodore Papadopoulo  <Theodore.Papadopoulo@sophia.inria.fr>
 
 	* src/misc-inst.cc: Remove unnecessary included files.

libstdc++-v3/docs/html/test.html

@@ -427,8 +427,8 @@ Example 4: Testing for compilation errors on line 41
 
 Example 5: Testing with special command line settings, or without the
 use of pre-compiled headers, in particular the stdc++.h.gch file. Any
-options here will override the DEFAULT_CXXFLAGS set up in the
-normal.exp file.
+options here will override the DEFAULT_CXXFLAGS and PCH_CXXFLAGS set
+up in the normal.exp file.
 // { dg-options "-O0" { target *-*-* } }
 </pre>
 

libstdc++-v3/testsuite/lib/libstdc++.exp

@@ -103,14 +103,7 @@ proc libstdc++_init { testfile } {
     # headers, or without assertions.
     global DEFAULT_CXXFLAGS
     if ![info exists DEFAULT_CXXFLAGS] then {
-	# Set up includes for stdc++.h.gch, the precompiled header file.
-	if { [file exists $flags_file] } {
-	    set cxxpchflags [exec sh $flags_file --cxxpchflags]
-	} else {
-	    set cxxpchflags ""
-	}
-	set DEFAULT_CXXFLAGS " ${cxxpchflags}"
-
+	set DEFAULT_CXXFLAGS ""
 	# Host specific goo here.
 	if { [string match "powerpc-*-darwin*" $target_triplet] } {
 	    append DEFAULT_CXXFLAGS " -multiply_defined suppress"
@@ -195,6 +188,28 @@ proc libstdc++_init { testfile } {
         }
     }
 
+    # If a PCH file is available, use it.  We must delay performing
+    # this check until $cxx and such have been initialized because we
+    # perform a test compilation.  (Ideally, gcc --print-file-name would
+    # list PCH files, but it does not.)
+    global PCH_CXXFLAGS
+    if ![info exists PCH_CXXFLAGS] then {
+	set src "config[pid].cc"
+	set f [open $src "w"]
+	puts $f "int main () {}"
+	close $f
+
+	set lines [v3_target_compile $src "config[pid].o" object \
+		   "additional_flags=-include additional_flags=bits/stdc++.h"]
+	if {$lines == "" } {
+	    set PCH_CXXFLAGS "-include bits/stdc++.h"
+	} else {
+	    set PCH_CXXFLAGS ""
+	}
+	file delete $src
+	v3track PCH_CXXFLAGS 2
+    }
+
     libstdc++_maybe_build_wrapper "${objdir}/testglue.o"
 }
 

libstdc++-v3/testsuite/libstdc++-dg/normal.exp

@@ -87,7 +87,8 @@ set tests [lsort $tests]
 
 # Main loop.
 global DEFAULT_CXXFLAGS
-dg-runtest $tests "" $DEFAULT_CXXFLAGS
+global PCH_CXXFLAGS
+dg-runtest $tests "" "$DEFAULT_CXXFLAGS $PCH_CXXFLAGS"
 
 # All done.
 dg-finish