Pre-processor mismatch between [libc/machine/arm] strlen.c and strlen-armv7.s - may lead in duplicate definition

[Markus Eisenmann]

Hi! 

I've got the situation, that the function strlen() occurs twice in libc.a (building newlib for ARM-V7a and Size-Optimized). 

In newlib/libc/machine/arm/strlen.c there are the pre-processor stetements ... 
#if defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED) || \
  (defined (__thumb__) && !defined (__thumb2__))
/*...*/ 
#else

#if !(defined(_ISA_ARM_7) || defined(__ARM_ARCH_6T2__)) 
/*...*/ 
#endif 

and in newlib/libc/machine/arm/strlen-armv7.S the "exclude" begins with

/* NOTE: This ifdef MUST match the ones in arm/strlen.c
   We fallback to the one in arm/strlen.c for size optimised or
   for older architectures. */
#if defined(_ISA_ARM_7) || defined(__ARM_ARCH_6T2__) && \
    !(defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED) || \
      (defined (__thumb__) && !defined (__thumb2__)))

But this is not completely contrary to arm/strlen.c (see above)!

To fix the logical statement in arm/strlen-armv7.S there are parentheses needed (in the first part):

----------------------------------------------
--- newlib/libc/machine/arm/strlen-armv7.S
+++ newlib/libc/machine/arm/strlen-armv7.S
@@ -37,7 +37,7 @@
 /* NOTE: This ifdef MUST match the ones in arm/strlen.c
    We fallback to the one in arm/strlen.c for size optimised or
    for older architectures. */
-#if defined(_ISA_ARM_7) || defined(__ARM_ARCH_6T2__) && \
+#if (defined(_ISA_ARM_7) || defined(__ARM_ARCH_6T2__)) && \
     !(defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED) || \
       (defined (__thumb__) && !defined (__thumb2__)))

----------------------------------------------

Best regards from Salzburg,
Markus