gdb: Have allocate_target_description return a unique_ptr

Update allocate_target_description to return a target_desc_up, a
specialisation of unique_ptr.

This commit does not attempt to make use of the unique_ptr in the
best possible way, in almost all cases we immediately release the
pointer from within the unique_ptr and then continue as before.

There are a few places where it was easy to handle the unique_ptr, and
in these cases I've done that.

Everything under gdb/features/* is auto-regenerated.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* arch/aarch32.c (aarch32_create_target_description): Release
	unique_ptr returned from allocate_target_description.
	* arch/aarch64.c (aarch64_create_target_description): Likewise.
	* arch/amd64.c (amd64_create_target_description): Likewise.
	* arch/arc.c (arc_create_target_description): Likewise.
	* arch/arm.c (arm_create_target_description): Likewise.
	* arch/i386.c (i386_create_target_description): Likewise.
	* arch/riscv.c (riscv_create_target_description): Update return
	type.  Handle allocate_target_description returning a unique_ptr.
	(riscv_lookup_target_description): Update to handle unique_ptr.
	* arch/tic6x.c (tic6x_create_target_description): Release
	unique_ptr returned from allocate_target_description.
	* features/microblaze-with-stack-protect.c: Regenerate.
	* features/microblaze.c: Regenerate.
	* features/mips-dsp-linux.c: Regenerate.
	* features/mips-linux.c: Regenerate.
	* features/mips64-dsp-linux.c: Regenerate.
	* features/mips64-linux.c: Regenerate.
	* features/nds32.c: Regenerate.
	* features/nios2.c: Regenerate.
	* features/or1k.c: Regenerate.
	* features/rs6000/powerpc-32.c: Regenerate.
	* features/rs6000/powerpc-32l.c: Regenerate.
	* features/rs6000/powerpc-403.c: Regenerate.
	* features/rs6000/powerpc-403gc.c: Regenerate.
	* features/rs6000/powerpc-405.c: Regenerate.
	* features/rs6000/powerpc-505.c: Regenerate.
	* features/rs6000/powerpc-601.c: Regenerate.
	* features/rs6000/powerpc-602.c: Regenerate.
	* features/rs6000/powerpc-603.c: Regenerate.
	* features/rs6000/powerpc-604.c: Regenerate.
	* features/rs6000/powerpc-64.c: Regenerate.
	* features/rs6000/powerpc-64l.c: Regenerate.
	* features/rs6000/powerpc-7400.c: Regenerate.
	* features/rs6000/powerpc-750.c: Regenerate.
	* features/rs6000/powerpc-860.c: Regenerate.
	* features/rs6000/powerpc-altivec32.c: Regenerate.
	* features/rs6000/powerpc-altivec32l.c: Regenerate.
	* features/rs6000/powerpc-altivec64.c: Regenerate.
	* features/rs6000/powerpc-altivec64l.c: Regenerate.
	* features/rs6000/powerpc-e500.c: Regenerate.
	* features/rs6000/powerpc-e500l.c: Regenerate.
	* features/rs6000/powerpc-isa205-32l.c: Regenerate.
	* features/rs6000/powerpc-isa205-64l.c: Regenerate.
	* features/rs6000/powerpc-isa205-altivec32l.c: Regenerate.
	* features/rs6000/powerpc-isa205-altivec64l.c: Regenerate.
	* features/rs6000/powerpc-isa205-ppr-dscr-vsx32l.c: Regenerate.
	* features/rs6000/powerpc-isa205-ppr-dscr-vsx64l.c: Regenerate.
	* features/rs6000/powerpc-isa205-vsx32l.c: Regenerate.
	* features/rs6000/powerpc-isa205-vsx64l.c: Regenerate.
	* features/rs6000/powerpc-isa207-htm-vsx32l.c: Regenerate.
	* features/rs6000/powerpc-isa207-htm-vsx64l.c: Regenerate.
	* features/rs6000/powerpc-isa207-vsx32l.c: Regenerate.
	* features/rs6000/powerpc-isa207-vsx64l.c: Regenerate.
	* features/rs6000/powerpc-vsx32.c: Regenerate.
	* features/rs6000/powerpc-vsx32l.c: Regenerate.
	* features/rs6000/powerpc-vsx64.c: Regenerate.
	* features/rs6000/powerpc-vsx64l.c: Regenerate.
	* features/rs6000/rs6000.c: Regenerate.
	* features/rx.c: Regenerate.
	* features/s390-gs-linux64.c: Regenerate.
	* features/s390-linux32.c: Regenerate.
	* features/s390-linux32v1.c: Regenerate.
	* features/s390-linux32v2.c: Regenerate.
	* features/s390-linux64.c: Regenerate.
	* features/s390-linux64v1.c: Regenerate.
	* features/s390-linux64v2.c: Regenerate.
	* features/s390-te-linux64.c: Regenerate.
	* features/s390-tevx-linux64.c: Regenerate.
	* features/s390-vx-linux64.c: Regenerate.
	* features/s390x-gs-linux64.c: Regenerate.
	* features/s390x-linux64.c: Regenerate.
	* features/s390x-linux64v1.c: Regenerate.
	* features/s390x-linux64v2.c: Regenerate.
	* features/s390x-te-linux64.c: Regenerate.
	* features/s390x-tevx-linux64.c: Regenerate.
	* features/s390x-vx-linux64.c: Regenerate.
	* mips-tdep.c (_initialize_mips_tdep): Release unique_ptr returned
	from allocate_target_description.
	* target-descriptions.c (allocate_target_description): Update
	return type.
	(print_c_tdesc::visit_pre): Release unique_ptr returned from
	allocate_target_description.

gdbserver/ChangeLog:

	* linux-low.cc (linux_process_target::handle_extended_wait):
	Release the unique_ptr returned from allocate_target_description.
	* linux-riscv-low.cc (riscv_target::low_arch_setup): Likewise.
	* linux-x86-low.cc (tdesc_amd64_linux_no_xml): Change type.
	(tdesc_i386_linux_no_xml): Change type.
	(x86_linux_read_description): Borrow pointer from unique_ptr
	object.
	(x86_target::get_ipa_tdesc_idx): Likewise.
	(initialize_low_arch): Likewise.
	* tdesc.cc (allocate_target_description): Update return type.

gdbsupport/ChangeLog:

	* tdesc.h (allocate_target_description): Update return type.

8 files changed, 22 insertions, 21 deletions

diff --git a/gdb/arch/aarch32.c b/gdb/arch/aarch32.c
index 5bc24a3..bf7a332 100644
--- a/gdb/arch/aarch32.c
+++ b/gdb/arch/aarch32.c
@@ -26,7 +26,7 @@
 target_desc *
 aarch32_create_target_description ()
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   set_tdesc_architecture (tdesc, "arm");
diff --git a/gdb/arch/aarch64.c b/gdb/arch/aarch64.c
index f611543..c0af7b0 100644
--- a/gdb/arch/aarch64.c
+++ b/gdb/arch/aarch64.c
@@ -29,7 +29,7 @@
 target_desc *
 aarch64_create_target_description (uint64_t vq, bool pauth_p)
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   set_tdesc_architecture (tdesc, "aarch64");
diff --git a/gdb/arch/amd64.c b/gdb/arch/amd64.c
index a388c7e..b11a4fd 100644
--- a/gdb/arch/amd64.c
+++ b/gdb/arch/amd64.c
@@ -40,7 +40,7 @@ target_desc *
 amd64_create_target_description (uint64_t xcr0, bool is_x32, bool is_linux,
 				 bool segments)
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   set_tdesc_architecture (tdesc, is_x32 ? "i386:x64-32" : "i386:x86-64");
diff --git a/gdb/arch/arc.c b/gdb/arch/arc.c
index 3808f9f..dff4575 100644
--- a/gdb/arch/arc.c
+++ b/gdb/arch/arc.c
@@ -38,7 +38,7 @@ STATIC_IN_GDB target_desc *
 arc_create_target_description (const struct arc_arch_features &features)
 {
   /* Create a new target description.  */
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   std::string arch_name;
diff --git a/gdb/arch/arm.c b/gdb/arch/arm.c
index faa2b4f..dc67e40 100644
--- a/gdb/arch/arm.c
+++ b/gdb/arch/arm.c
@@ -374,7 +374,7 @@ shifted_reg_val (struct regcache *regcache, unsigned long inst,
 target_desc *
 arm_create_target_description (arm_fp_type fp_type)
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   if (fp_type == ARM_FP_TYPE_IWMMXT)
@@ -416,7 +416,7 @@ arm_create_target_description (arm_fp_type fp_type)
 target_desc *
 arm_create_mprofile_target_description (arm_m_profile_type m_type)
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   set_tdesc_architecture (tdesc, "arm");
diff --git a/gdb/arch/i386.c b/gdb/arch/i386.c
index 099a20b..13201db 100644
--- a/gdb/arch/i386.c
+++ b/gdb/arch/i386.c
@@ -35,7 +35,7 @@
 target_desc *
 i386_create_target_description (uint64_t xcr0, bool is_linux, bool segments)
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
 #ifndef IN_PROCESS_AGENT
   set_tdesc_architecture (tdesc, "i386");
diff --git a/gdb/arch/riscv.c b/gdb/arch/riscv.c
index 8f57090..a6538de 100644
--- a/gdb/arch/riscv.c
+++ b/gdb/arch/riscv.c
@@ -33,11 +33,11 @@
 
 /* See arch/riscv.h.  */
 
-STATIC_IN_GDB target_desc *
+STATIC_IN_GDB target_desc_up
 riscv_create_target_description (const struct riscv_gdbarch_features features)
 {
   /* Now we should create a new target description.  */
-  target_desc *tdesc = allocate_target_description ();
+  target_desc_up tdesc = allocate_target_description ();
 
 #ifndef IN_PROCESS_AGENT
   std::string arch_name = "riscv";
@@ -56,22 +56,22 @@ riscv_create_target_description (const struct riscv_gdbarch_features features)
   else if (features.flen == 16)
     arch_name.append ("q");
 
-  set_tdesc_architecture (tdesc, arch_name.c_str ());
+  set_tdesc_architecture (tdesc.get (), arch_name.c_str ());
 #endif
 
   long regnum = 0;
 
   /* For now we only support creating 32-bit or 64-bit x-registers.  */
   if (features.xlen == 4)
-    regnum = create_feature_riscv_32bit_cpu (tdesc, regnum);
+    regnum = create_feature_riscv_32bit_cpu (tdesc.get (), regnum);
   else if (features.xlen == 8)
-    regnum = create_feature_riscv_64bit_cpu (tdesc, regnum);
+    regnum = create_feature_riscv_64bit_cpu (tdesc.get (), regnum);
 
   /* For now we only support creating 32-bit or 64-bit f-registers.  */
   if (features.flen == 4)
-    regnum = create_feature_riscv_32bit_fpu (tdesc, regnum);
+    regnum = create_feature_riscv_32bit_fpu (tdesc.get (), regnum);
   else if (features.flen == 8)
-    regnum = create_feature_riscv_64bit_fpu (tdesc, regnum);
+    regnum = create_feature_riscv_64bit_fpu (tdesc.get (), regnum);
 
   return tdesc;
 }
@@ -106,13 +106,14 @@ riscv_lookup_target_description (const struct riscv_gdbarch_features features)
   if (it != riscv_tdesc_cache.end ())
     return it->second.get ();
 
-  target_desc *tdesc = riscv_create_target_description (features);
+  target_desc_up tdesc (riscv_create_target_description (features));
 
-  /* Add to the cache.  Work around a problem with g++ 4.8 (PR96537):
-     Call the target_desc_up constructor explictly instead of implicitly.  */
-  riscv_tdesc_cache.emplace (features, target_desc_up (tdesc));
-
-  return tdesc;
+  /* Add to the cache, and return a pointer borrowed from the
+     target_desc_up.  This is safe as the cache (and the pointers
+     contained within it) are not deleted until GDB exits.  */
+  target_desc *ptr = tdesc.get ();
+  riscv_tdesc_cache.emplace (features, std::move (tdesc));
+  return ptr;
 }
 
 #endif /* !GDBSERVER */
diff --git a/gdb/arch/tic6x.c b/gdb/arch/tic6x.c
index 5f14d34..dad4dd8 100644
--- a/gdb/arch/tic6x.c
+++ b/gdb/arch/tic6x.c
@@ -28,7 +28,7 @@
 target_desc *
 tic6x_create_target_description (enum c6x_feature feature)
 {
-  target_desc *tdesc = allocate_target_description ();
+  target_desc *tdesc = allocate_target_description ().release ();
 
   set_tdesc_architecture (tdesc, "tic6x");
   set_tdesc_osabi (tdesc, "GNU/Linux");