Kconfig files, binfmt/libelf, libs/libc/machin, libs/libxx: Correct libcxx exception handling by introducing the generic config(CXX_EXCEPTION and CXX_LIBSUPCXX)

arch/arm/src/armv7-m/Kconfig

@@ -211,8 +211,8 @@ config ARMV7M_OABI_TOOLCHAIN
 
 config ARMV7M_TARGET2_PREL
 	bool "R_ARM_TARGET2 is PC relative"
-	default n if !UCLIBCXX_EXCEPTION
+	default n if !CXX_EXCEPTION
-	default y if UCLIBCXX_EXCEPTION
+	default y if CXX_EXCEPTION
 	depends on ELF
 	---help---
 		Perform a PC relative relocation for relocation type R_ARM_TARGET2

binfmt/libelf/Kconfig

@@ -42,7 +42,7 @@ config ELF_DUMPBUFFER
 config ELF_EXIDX_SECTNAME
 	string "ELF Section Name for Exception Index"
 	default ".ARM.exidx"
-	depends on UCLIBCXX_EXCEPTION
+	depends on CXX_EXCEPTION
 	---help---
 		Set the name string for the exception index section on the ELF modules to
 		be loaded by the ELF binary loader.

binfmt/libelf/libelf_load.c

@@ -244,7 +244,7 @@ static inline int elf_loadfile(FAR struct elf_loadinfo_s *loadinfo)
 int elf_load(FAR struct elf_loadinfo_s *loadinfo)
 {
   size_t heapsize;
-#ifdef CONFIG_UCLIBCXX_EXCEPTION
+#ifdef CONFIG_CXX_EXCEPTION
   int exidx;
 #endif
   int ret;
@@ -330,7 +330,7 @@ int elf_load(FAR struct elf_loadinfo_s *loadinfo)
     }
 #endif
 
-#ifdef CONFIG_UCLIBCXX_EXCEPTION
+#ifdef CONFIG_CXX_EXCEPTION
   exidx = elf_findsection(loadinfo, CONFIG_ELF_EXIDX_SECTNAME);
   if (exidx < 0)
     {

libs/libc/machine/arm/armv7-m/arch_elf.c

@@ -46,14 +46,6 @@
 #include <arch/elf.h>
 #include <nuttx/elf.h>
 
-/****************************************************************************
- * Public Function Prototypes
- ****************************************************************************/
-
-#ifdef CONFIG_UCLIBCXX_EXCEPTION
-extern void init_unwind_exidx(Elf32_Addr start, Elf32_Addr end);
-#endif
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -472,13 +464,3 @@ int up_relocateadd(FAR const Elf32_Rela *rel, FAR const Elf32_Sym *sym,
   berr("ERROR: RELA relocation not supported\n");
   return -ENOSYS;
 }
-
-#ifdef CONFIG_UCLIBCXX_EXCEPTION
-int up_init_exidx(Elf32_Addr address, Elf32_Word size)
-{
-  init_unwind_exidx(address, size);
-
-  return OK;
-}
-#endif
-

libs/libxx/Kconfig

@@ -30,6 +30,12 @@ config CXX_NEWLONG
 		C++ library routines because the NuttX size_t might not have
 		the same underlying type as your toolchain's size_t.
 
+config CXX_EXCEPTION
+	bool
+
+config CXX_LIBSUPCXX
+	bool
+
 comment "LLVM C++ Library (libcxx)"
 
 config LIBCXX
@@ -45,14 +51,12 @@ if LIBCXX
 config LIBCXX_EXCEPTION
 	bool "Enable Exception Suppport"
 	default y
-
+	select CXX_EXCEPTION
-config LIBCXX_IOSTREAM_BUFSIZE
-	int "IO Stream Buffer Size"
-	default 32
 
 config LIBCXX_HAVE_LIBSUPCXX
 	bool "Have libsupc++ (required)"
 	default y
+	select CXX_LIBSUPCXX
 	---help---
 		Select if your toolchain provides libsupc++.  This option is required
 		at present because the built-in libsupc++ support is incomplete.
@@ -74,6 +78,7 @@ if UCLIBCXX
 config UCLIBCXX_EXCEPTION
 	bool "Enable Exception Suppport"
 	default y
+	select CXX_EXCEPTION
 
 config UCLIBCXX_IOSTREAM_BUFSIZE
 	int "IO Stream Buffer Size"
@@ -82,6 +87,7 @@ config UCLIBCXX_IOSTREAM_BUFSIZE
 config UCLIBCXX_HAVE_LIBSUPCXX
 	bool "Have libsupc++ (required)"
 	default y
+	select CXX_LIBSUPCXX
 	---help---
 		Select if your toolchain provides libsupc++.  This option is required
 		at present because the built-in libsupc++ support is incomplete.

libs/libxx/Makefile

@@ -47,7 +47,7 @@ ASRCS =
 CSRCS =
 
 CXXSRCS  = libxx_cxapurevirtual.cxx libxx_eabi_atexit.cxx  libxx_cxa_atexit.cxx
-ifneq (,$(findstring y,$(CONFIG_UCLIBCXX_EXCEPTION) $(CONFIG_LIBCXX_EXCEPTION)))
+ifeq ($(CONFIG_CXX_EXCEPTION),y)
 CXXSRCS += libxx__gnu_unwind_find_exidx.cxx
 endif
 
@@ -58,10 +58,6 @@ ifeq (,$(findstring y,$(CONFIG_UCLIBCXX) $(CONFIG_LIBCXX)))
 CXXSRCS += libxx_delete.cxx libxx_delete_sized.cxx libxx_deletea.cxx
 CXXSRCS += libxx_deletea_sized.cxx libxx_new.cxx libxx_newa.cxx
 CXXSRCS += libxx_stdthrow.cxx
-else
-ifeq (,$(findstring y,$(CONFIG_UCLIBCXX_EXCEPTION) $(CONFIG_LIBCXX_EXCEPTION)))
-CXXSRCS += libxx_stdthrow.cxx
-endif
 endif
 
 # uClibc++ doesn't need this file

libs/libxx/libxx__gnu_unwind_find_exidx.cxx

@@ -37,6 +37,7 @@
 // Included Files
 //***************************************************************************
 
+#include <nuttx/elf.h>
 #include "libxx__gnu_unwind_find_exidx.hxx"
 
 //***************************************************************************
@@ -84,10 +85,11 @@
 
 extern "C"
 {
-  void init_unwind_exidx(Elf32_Addr start, Elf32_Word size)
+  int up_init_exidx(Elf32_Addr start, Elf32_Word size)
   {
     __exidx_start_elf = (__EIT_entry *) start;
     __exidx_end_elf   = __exidx_start_elf + size;
+    return 0;
   }
 
   _Unwind_Ptr __gnu_Unwind_Find_exidx (_Unwind_Ptr return_address, int *nrecp)

libs/libxx/libxx__gnu_unwind_find_exidx.hxx

@@ -42,7 +42,6 @@ extern "C"
 // Included Files
 //***************************************************************************
 
-#include <elf32.h>
 #include <unwind.h>
 
 //***************************************************************************