Re: Prefixes for libgcc symbols (C6X 9.5/11)

[Bernd Schmidt]

On 05/25/2011 01:45 PM, H.J. Lu wrote:
> On Wed, May 25, 2011 at 6:42 AM, Bernd Schmidt <ber...@codesourcery.com> 
> wrote:
>> On 05/25/2011 01:37 PM, H.J. Lu wrote:
>>
>>> I think it may have caused:
>>>
>>> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49160
>>
>> Looks like it. Not quite sure how to fix it yet. Do you know what files
>> such as i386/64/_divtc3.c are trying to achieve?
>>
> 
> It provides backward compatibility with symbol versioning:
> 
> [hjl@gnu-4 64]$ readelf -s /lib64/libgcc_s.so.1| grep __powitf2
>     52: 0000003e8a80d170   167 FUNC    GLOBAL DEFAULT   12 
> __powitf2@@GCC_4.3.0
>     54: 0000003e8a80d170   167 FUNC    GLOBAL DEFAULT   12 __powitf2@GCC_4.0.0
> [hjl@gnu-4 64]$

That leaves me as clueless as before. Why does i386/64 need this but not
other targets (such as i386/32), and why only those three functions
(from the ones in libgcc)?

Anyhow, below is one possible way of fixing it.


Bernd


        PR bootstrap/49160
        * libgcc2.h (__powisf2, __powidf2, __powitf2, __powixf2,
        __mulsc3, __muldc3, __mulxc3, __multc3, __divsc3, __divdc3,
        __divxc3, __divtc3): Wrap definitions in #ifndef.

Index: gcc/libgcc2.h
===================================================================
--- gcc/libgcc2.h       (revision 174187)
+++ gcc/libgcc2.h       (working copy)
@@ -324,23 +324,48 @@ typedef int shift_count_type __attribute
 #define __parityDI2    __NDW(parity,2)
 
 #define __clz_tab              __N(clz_tab)
+#define __bswapsi2             __N(bswapsi2)
+#define __bswapdi2             __N(bswapdi2)
+#define __udiv_w_sdiv          __N(udiv_w_sdiv)
+#define __clear_cache          __N(clear_cache)
+#define __enable_execute_stack __N(enable_execute_stack)
+
+#ifndef __powisf2
 #define __powisf2              __N(powisf2)
+#endif
+#ifndef __powidf2
 #define __powidf2              __N(powidf2)
+#endif
+#ifndef __powitf2
 #define __powitf2              __N(powitf2)
+#endif
+#ifndef __powixf2
 #define __powixf2              __N(powixf2)
-#define __bswapsi2             __N(bswapsi2)
-#define __bswapdi2             __N(bswapdi2)
+#endif
+#ifndef __mulsc3
 #define __mulsc3               __N(mulsc3)
+#endif
+#ifndef __muldc3
 #define __muldc3               __N(muldc3)
+#endif
+#ifndef __mulxc3
 #define __mulxc3               __N(mulxc3)
+#endif
+#ifndef __multc3
 #define __multc3               __N(multc3)
+#endif
+#ifndef __divsc3
 #define __divsc3               __N(divsc3)
+#endif
+#ifndef __divdc3
 #define __divdc3               __N(divdc3)
+#endif
+#ifndef __divxc3
 #define __divxc3               __N(divxc3)
+#endif
+#ifndef __divtc3
 #define __divtc3               __N(divtc3)
-#define __udiv_w_sdiv          __N(udiv_w_sdiv)
-#define __clear_cache          __N(clear_cache)
-#define __enable_execute_stack __N(enable_execute_stack)
+#endif
 
 extern DWtype __muldi3 (DWtype, DWtype);
 extern DWtype __divdi3 (DWtype, DWtype);