diff --git a/source/m3_config_platforms.h b/source/m3_config_platforms.h
index 13f026a..bbb541c 100644
--- a/source/m3_config_platforms.h
+++ b/source/m3_config_platforms.h
@@ -48,7 +48,7 @@
 #   define M3_ARCH "x86_64"
 
 #  elif defined(__i386__)
-#   define M3_ARCH "x86"
+#   define M3_ARCH "i386"
 
 #  elif defined(__aarch64__)
 #   define M3_ARCH "arm64-v8a"
@@ -158,9 +158,9 @@
 
 # if defined(M3_COMPILER_MSVC)
 #  if defined(_M_X64)
-#   define M3_ARCH "x64"
+#   define M3_ARCH "x86_64"
 #  elif defined(_M_IX86)
-#   define M3_ARCH "x86"
+#   define M3_ARCH "i386"
 #  elif defined(_M_ARM64)
 #   define M3_ARCH "arm64"
 #  elif defined(_M_ARM)
diff --git a/test/run-spec-test.py b/test/run-spec-test.py
index 750851f..84a1313 100755
--- a/test/run-spec-test.py
+++ b/test/run-spec-test.py
@@ -304,7 +304,7 @@ blacklist = Blacklist([
   "names.wast:* *.wasm \\x00*", # names that start with '\0'
 ])
 
-if wasm3_ver in Blacklist(["* on x86\n* MSVC *", "* on x86\n* Clang * for Windows"]):
+if wasm3_ver in Blacklist(["* on i386* MSVC *", "* on i386* Clang * for Windows"]):
     warning("Win32 x86 has i64->f32 conversion precision issues, skipping some tests", True)
     # See: https://docs.microsoft.com/en-us/cpp/c-runtime-library/floating-point-support
     blacklist.add([