Re: [Patch, driver] PR41594 recognize -static-libstdc++ as a valid option.

[Dave Korn <dave dot korn dot cygwin at googlemail dot com>]

IainS wrote:
> 
> On 5 Oct 2009, at 21:06, Dave Korn wrote:
> 
>> IainS wrote:
>>> The driver currently rejects -static-libstdc++ although it is processed
>>> by g++spec.c
>>
>>   Do you perhaps mean when invoked as 'gcc' rather than as 'g++'?
> 
> yes, which causes a couple of fails if one tries to run the testsuite
> with /-static-libstdc++

  If I understand your patch correctly, it will cause gcc to accept but ignore
the option, yes?  Out of curiosity, here's part of a patch I submitted earlier
to much the same end.  It has the minor additional feature that even when
using g++, you can test for -static-libstdc++ in specs (normally g++spec.c
cuts it out), and apart from that it uses a spec to allow-and-ignore the
option in the same way as -static.  Can you see any practical differences
between the two approaches (i.e. ignoring it in a spec, vs. extending the
if-test that sets the validated flag)?

    cheers,
      DaveK

Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c	(revision 152230)
+++ gcc/gcc.c	(working copy)
@@ -760,7 +760,10 @@ proper position among the other output files.  */
 
 /* -u* was put back because both BSD and SysV seem to support it.  */
 /* %{static:} simply prevents an error message if the target machine
-   doesn't handle -static.  */
+   doesn't handle -static; %{static-libstdc++} is not handled by any
+   target machine but entirely in cp/g++spec.c, yet we cannot just
+   remove it from the command-line there or it cannot be tested in
+   spec processing, so we simply ignore it here similarly.  */
 /* We want %{T*} after %{L*} and %D so that it can be used to specify linker
    scripts which exist in user specified directories, or in standard
    directories.  */
@@ -769,7 +772,7 @@ proper position among the other output files.  */
 %{!fsyntax-only:%{!c:%{!M:%{!MM:%{!E:%{!S:\
     %(linker) %l " LINK_PIE_SPEC "%X %{o*} %{A} %{d} %{e*} %{m} %{N} %{n} %{r}\
     %{s} %{t} %{u*} %{x} %{z} %{Z} %{!A:%{!nostdlib:%{!nostartfiles:%S}}}\
-    %{static:} %{L*} %(mfwrap) %(link_libgcc) %o\
+    %{static:} %{static-libstdc++:} %{L*} %(mfwrap) %(link_libgcc) %o\
     %{fopenmp|ftree-parallelize-loops=*:%:include(libgomp.spec)%(link_gomp)} %(mflib)\
     %{fprofile-arcs|fprofile-generate*|coverage:-lgcov}\
     %{!nostdlib:%{!nodefaultlibs:%(link_ssp) %(link_gcc_c_sequence)}}\
Index: gcc/cp/g++spec.c
===================================================================
--- gcc/cp/g++spec.c	(revision 152230)
+++ gcc/cp/g++spec.c	(working copy)
@@ -30,8 +30,6 @@ along with GCC; see the file COPYING3.  If not see
 #define MATHLIB		(1<<2)
 /* This bit is set if they did `-lc'.  */
 #define WITHLIBC	(1<<3)
-/* Skip this option.  */
-#define SKIPOPT		(1<<4)
 
 #ifndef MATH_LIBRARY
 #define MATH_LIBRARY "-lm"
@@ -211,10 +209,7 @@ lang_specific_driver (int *in_argc, const char *co
 	  else if (strcmp (argv[i], "-static-libgcc") == 0)
 	    shared_libgcc = 0;
 	  else if (strcmp (argv[i], "-static-libstdc++") == 0)
-	    {
 	      library = library >= 0 ? 2 : library;
-	      args[i] |= SKIPOPT;
-	    }
 	  else if (DEFAULT_WORD_SWITCH_TAKES_ARG (&argv[i][1]))
 	    i++;
 	  else
@@ -324,9 +319,6 @@ lang_specific_driver (int *in_argc, const char *co
 	  arglist[j] = "-xnone";
 	}
 
-      if ((args[i] & SKIPOPT) != 0)
-	--j;
-
       i++;
       j++;
     }