Attempt to fix endian test for Emscripten.

Author: nascheme

Tools/configure/pyconf.py

@@ -2886,10 +2886,20 @@ def ax_c_float_words_bigendian(
             if callable(on_unknown):
                 on_unknown()
             return
-        # Read the linked binary and look for the marker strings.
-        try:
-            data = open(exe_path, "rb").read()
-        except OSError:
+        # Read all conftest* output files and look for the marker strings.
+        # Autoconf uses "grep noonsees conftest*" which globs all outputs;
+        # this is important for Emscripten where the compiler may produce
+        # conftest.js + conftest.wasm instead of a single conftest binary.
+        data = b""
+        for name in os.listdir(tmp):
+            if not name.startswith("conftest") or name == "conftest.c":
+                continue
+            path = os.path.join(tmp, name)
+            try:
+                data += open(path, "rb").read()
+            except OSError:
+                pass
+        if not data:
             if callable(on_unknown):
                 on_unknown()
             return

Tools/configure/transpiler/pyconf.awk

@@ -2027,13 +2027,13 @@ function pyconf_ax_c_float_words_bigendian(on_big, on_little, on_unknown, src, c
         cmd = cmd V["CC"] " " V["CPPFLAGS"] " " V["CFLAGS"] " " V["LDFLAGS"] " " conftest " -o " exe " " V["LIBS"] " 2>/dev/null"
         rc = system(cmd)
         if (rc != 0) {
-                system("rm -f " conftest " " exe)
+                system("rm -f " _pyconf_tmpdir "/conftest*")
                 _pyconf_retval = "unknown"
                 return
         }
-        has_big = (system("grep -c noonsees " exe " >/dev/null 2>&1") == 0)
-        has_little = (system("grep -c seesnoon " exe " >/dev/null 2>&1") == 0)
-        system("rm -f " conftest " " exe)
+        has_big = (system("grep -c noonsees " _pyconf_tmpdir "/conftest* >/dev/null 2>&1") == 0)
+        has_little = (system("grep -c seesnoon " _pyconf_tmpdir "/conftest* >/dev/null 2>&1") == 0)
+        system("rm -f " _pyconf_tmpdir "/conftest*")
         if (has_big && !has_little)
                 _pyconf_retval = "big"
         else if (has_little && !has_big)