[ARM] PR target/78253 Call weak function instead of strong when called through pointer.

2017-01-11  Christophe Lyon  <christophe.lyon@linaro.org>

	PR target/78253
	* config/arm/arm.c (legitimize_pic_address): Handle reference to
	weak symbol.
	(arm_assemble_integer): Likewise.

From-SVN: r244320

gcc/ChangeLog

+2017-01-11  Christophe Lyon  <christophe.lyon@linaro.org>
+
+	PR target/78253
+	* config/arm/arm.c (legitimize_pic_address): Handle reference to
+	weak symbol.
+	(arm_assemble_integer): Likewise.
+
 2017-01-11  Richard Earnshaw  <rearnsha@arm.com>
 
 	* config.gcc: Use new awk script to check CPU, FPU and architecture

gcc/config/arm/arm.c

@@ -7269,10 +7269,14 @@ legitimize_pic_address (rtx orig, machine_mode mode, rtx reg)
 	 same segment as the GOT.  Unfortunately, the flexibility of linker
 	 scripts means that we can't be sure of that in general, so assume
 	 that GOTOFF is never valid on VxWorks.  */
+      /* References to weak symbols cannot be resolved locally: they
+	 may be overridden by a non-weak definition at link time.  */
       rtx_insn *insn;
       if ((GET_CODE (orig) == LABEL_REF
-	   || (GET_CODE (orig) == SYMBOL_REF &&
-	       SYMBOL_REF_LOCAL_P (orig)))
+	   || (GET_CODE (orig) == SYMBOL_REF
+	       && SYMBOL_REF_LOCAL_P (orig)
+	       && (SYMBOL_REF_DECL (orig)
+		   ? !DECL_WEAK (SYMBOL_REF_DECL (orig)) : 1)))
 	  && NEED_GOT_RELOC
 	  && arm_pic_data_is_text_relative)
 	insn = arm_pic_static_addr (orig, reg);
@@ -22475,8 +22479,14 @@ arm_assemble_integer (rtx x, unsigned int size, int aligned_p)
 	{
 	  /* See legitimize_pic_address for an explanation of the
 	     TARGET_VXWORKS_RTP check.  */
+	  /* References to weak symbols cannot be resolved locally:
+	     they may be overridden by a non-weak definition at link
+	     time.  */
 	  if (!arm_pic_data_is_text_relative
-	      || (GET_CODE (x) == SYMBOL_REF && !SYMBOL_REF_LOCAL_P (x)))
+	      || (GET_CODE (x) == SYMBOL_REF
+		  && (!SYMBOL_REF_LOCAL_P (x)
+		      || (SYMBOL_REF_DECL (x)
+			  ? DECL_WEAK (SYMBOL_REF_DECL (x)) : 0))))
 	    fputs ("(GOT)", asm_out_file);
 	  else
 	    fputs ("(GOTOFF)", asm_out_file);