Merge bitcoin/bitcoin#25612: depends: default to using GCC tool wrappers for LTO (with GCC)

658685a depends: default to using GCC tool wrappers (with GCC) (fanquake)
6fdc13c build: Fix autoconf variable names for tools found by `AC_PATH_TOOL` (Hennadii Stepanov)

Pull request description:

  This improves support for LTO by using gcc wrappers for `ar`, `nm`, `ranlib`,
  that correctly setup plugin arguments for LTO, when using GCC.

  Other HOSTS are using clang.

  Portion of #25391.

  Guix Build (x86_64):
  ```bash
  ```

  Guix Build (arm64):
  ```bash
  ```

ACKs for top commit:
  dongcarl:
    Code Review ACK 658685a
  hebasto:
    ACK 658685a
  jarolrod:
    ACK 658685a

Tree-SHA512: 28d6127c118f74336c97e2523117f8a0d11b32cd565124cd4052baeb7cc53e71909d3037cb080d996ae4e3ce600326fced37ee36adcc53d839ba7dd7974ebcd2

Author: fanquake

configure.ac

@@ -2049,5 +2049,6 @@ echo "  CPPFLAGS        = $DEBUG_CPPFLAGS $HARDENED_CPPFLAGS $CORE_CPPFLAGS $CPP
 echo "  CXX             = $CXX"
 echo "  CXXFLAGS        = $LTO_CXXFLAGS $DEBUG_CXXFLAGS $HARDENED_CXXFLAGS $WARN_CXXFLAGS $NOWARN_CXXFLAGS $ERROR_CXXFLAGS $GPROF_CXXFLAGS $CORE_CXXFLAGS $CXXFLAGS"
 echo "  LDFLAGS         = $LTO_LDFLAGS $PTHREAD_LIBS $HARDENED_LDFLAGS $GPROF_LDFLAGS $CORE_LDFLAGS $LDFLAGS"
+echo "  AR              = $AR"
 echo "  ARFLAGS         = $ARFLAGS"
 echo

depends/config.site.in

@@ -105,7 +105,7 @@ PYTHONPATH="${depends_prefix}/native/lib/python3/dist-packages${PYTHONPATH:+${PA
 
 if test -n "@AR@"; then
   AR="@AR@"
-  ac_cv_path_ac_pt_AR="${AR}"
+  ac_cv_path_AR="${AR}"
 fi
 
 if test -n "@RANLIB@"; then
@@ -126,17 +126,17 @@ fi
 if test "@host_os@" = darwin; then
   if test -n "@OTOOL@"; then
     OTOOL="@OTOOL@"
-    ac_cv_path_ac_pt_OTOOL="${OTOOL}"
+    ac_cv_path_OTOOL="${OTOOL}"
   fi
 
   if test -n "@INSTALL_NAME_TOOL@"; then
     INSTALL_NAME_TOOL="@INSTALL_NAME_TOOL@"
-    ac_cv_path_ac_pt_INSTALL_NAME_TOOL="${INSTALL_NAME_TOOL}"
+    ac_cv_path_INSTALL_NAME_TOOL="${INSTALL_NAME_TOOL}"
   fi
 
   if test -n "@DSYMUTIL@"; then
     DSYMUTIL="@DSYMUTIL@"
-    ac_cv_path_ac_pt_DSYMUTIL="${DSYMUTIL}"
+    ac_cv_path_DSYMUTIL="${DSYMUTIL}"
   fi
 fi
 

depends/hosts/linux.mk

@@ -5,6 +5,10 @@ ifneq ($(LTO),)
 linux_CFLAGS += -flto
 linux_CXXFLAGS += -flto
 linux_LDFLAGS += -flto
+
+linux_AR = $(host_toolchain)gcc-ar
+linux_NM = $(host_toolchain)gcc-nm
+linux_RANLIB = $(host_toolchain)gcc-ranlib
 endif
 
 linux_release_CFLAGS=-O2

depends/hosts/mingw32.mk

@@ -9,6 +9,10 @@ ifneq ($(LTO),)
 mingw32_CFLAGS += -flto
 mingw32_CXXFLAGS += -flto
 mingw32_LDFLAGS += -flto
+
+mingw32_AR = $(host_toolchain)gcc-ar
+mingw32_NM = $(host_toolchain)gcc-nm
+mingw32_RANLIB = $(host_toolchain)gcc-ranlib
 endif
 
 mingw32_release_CFLAGS=-O2

depends/hosts/netbsd.mk

@@ -5,6 +5,10 @@ ifneq ($(LTO),)
 netbsd_CFLAGS += -flto
 netbsd_CXXFLAGS += -flto
 netbsd_LDFLAGS += -flto
+
+netbsd_AR = $(host_toolchain)gcc-ar
+netbsd_NM = $(host_toolchain)gcc-nm
+netbsd_RANLIB = $(host_toolchain)gcc-ranlib
 endif
 
 netbsd_CXXFLAGS=$(netbsd_CFLAGS)