diff --git a/configure b/configure
index fcef4bd..97affb4 100755
--- a/configure
+++ b/configure
@@ -8122,7 +8122,7 @@ else $as_nop
        case "$gl_cv_host_cpu_c_abi" in
          i386 | x86_64-x32 | arm | armhf | arm64-ilp32 | hppa | ia64-ilp32 | mips | mipsn32 | powerpc | riscv*-ilp32* | s390 | sparc)
            gl_cv_host_cpu_c_abi_32bit=yes ;;
-         x86_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
+         x86_64 | sw_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
            gl_cv_host_cpu_c_abi_32bit=no ;;
          *)
            gl_cv_host_cpu_c_abi_32bit=unknown ;;
@@ -8151,7 +8151,7 @@ else $as_nop
            ;;
 
          # CPUs that only support a 64-bit ABI.
-         alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
+         sw_64* | alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
          | mmix )
            gl_cv_host_cpu_c_abi_32bit=no
            ;;
diff --git a/extension/configure b/extension/configure
index d8cf11d..1b424bd 100755
--- a/extension/configure
+++ b/extension/configure
@@ -5705,7 +5705,7 @@ else $as_nop
        case "$gl_cv_host_cpu_c_abi" in
          i386 | x86_64-x32 | arm | armhf | arm64-ilp32 | hppa | ia64-ilp32 | mips | mipsn32 | powerpc | riscv*-ilp32* | s390 | sparc)
            gl_cv_host_cpu_c_abi_32bit=yes ;;
-         x86_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
+         x86_64 | sw_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
            gl_cv_host_cpu_c_abi_32bit=no ;;
          *)
            gl_cv_host_cpu_c_abi_32bit=unknown ;;
@@ -5734,7 +5734,7 @@ else $as_nop
            ;;
 
          # CPUs that only support a 64-bit ABI.
-         alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
+         sw_64* | alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
          | mmix )
            gl_cv_host_cpu_c_abi_32bit=no
            ;;
diff --git a/m4/host-cpu-c-abi.m4 b/m4/host-cpu-c-abi.m4
index 6db2aa2..2244bc4 100644
--- a/m4/host-cpu-c-abi.m4
+++ b/m4/host-cpu-c-abi.m4
@@ -90,6 +90,12 @@ changequote([,])dnl
            [gl_cv_host_cpu_c_abi=i386])
          ;;
 
+changequote(,)dnl
+       sw_64* )
+changequote([,])dnl
+         gl_cv_host_cpu_c_abi=sw_64
+         ;;
+
 changequote(,)dnl
        alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] )
 changequote([,])dnl
@@ -355,6 +361,9 @@ EOF
 #ifndef __x86_64__
 #undef __x86_64__
 #endif
+#ifndef __sw_64__
+#undef __sw_64__
+#endif
 #ifndef __alpha__
 #undef __alpha__
 #endif
@@ -468,7 +477,7 @@ AC_DEFUN([gl_HOST_CPU_C_ABI_32BIT],
        case "$gl_cv_host_cpu_c_abi" in
          i386 | x86_64-x32 | arm | armhf | arm64-ilp32 | hppa | ia64-ilp32 | mips | mipsn32 | powerpc | riscv*-ilp32* | s390 | sparc)
            gl_cv_host_cpu_c_abi_32bit=yes ;;
-         x86_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
+         x86_64 | sw_64 | alpha | arm64 | hppa64 | ia64 | mips64 | powerpc64 | powerpc64-elfv2 | riscv*-lp64* | s390x | sparc64 )
            gl_cv_host_cpu_c_abi_32bit=no ;;
          *)
            gl_cv_host_cpu_c_abi_32bit=unknown ;;
@@ -498,7 +507,7 @@ AC_DEFUN([gl_HOST_CPU_C_ABI_32BIT],
 
          # CPUs that only support a 64-bit ABI.
 changequote(,)dnl
-         alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
+         sw_64* | alpha | alphaev[4-8] | alphaev56 | alphapca5[67] | alphaev6[78] \
          | mmix )
 changequote([,])dnl
            gl_cv_host_cpu_c_abi_32bit=no
diff --git a/m4/intdiv0.m4 b/m4/intdiv0.m4
index 44f9863..b4d17bb 100644
--- a/m4/intdiv0.m4
+++ b/m4/intdiv0.m4
@@ -69,7 +69,7 @@ int main ()
             # Guess based on the CPU.
 changequote(,)dnl
             case "$host_cpu" in
-              alpha* | i[34567]86 | x86_64 | m68k | s390*)
+              sw_64* | alpha* | i[34567]86 | x86_64 | m68k | s390*)
                 gt_cv_int_divbyzero_sigfpe="guessing yes";;
               *)
                 gt_cv_int_divbyzero_sigfpe="guessing no";;