[libc-commits] [libc] [libc][test] make `str_to_float_comparison_test` independent of C++ headers. (PR #133978)

[via libc-commits]

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@@ -59,30 +57,32 @@ int checkFile(char *inputFileName, int *totalFails, int *totalBitDiffs,
   int32_t curFails = 0;    // Only counts actual failures, not bitdiffs.
   int32_t curBitDiffs = 0; // A bitdiff is when the expected result and actual
                            // result are off by +/- 1 bit.
-  std::string line;
-  std::string num;
+  char *line = nullptr;
+  char *num = nullptr;
 
-  std::ifstream fileStream(inputFileName, std::ifstream::in);
+  auto *fileHandle = LIBC_NAMESPACE::fopen(inputFileName, "r");
 
-  if (!fileStream.is_open()) {
-    std::cout << "file '" << inputFileName << "' failed to open. Exiting.\n";
+  if (!fileHandle) {
+    LIBC_NAMESPACE::printf("file '%s' failed to open. Exiting.\n",
+                           inputFileName);
     return 1;
   }
-  while (getline(fileStream, line)) {
+
+  while (LIBC_NAMESPACE::fgets(line, 100, fileHandle)) {
     if (line[0] == '#') {
       continue;
     }
     *total = *total + 1;
     uint32_t expectedFloatRaw;
     uint64_t expectedDoubleRaw;
 
-    expectedFloatRaw = fastHexToU32(line.c_str() + 5);
-    expectedDoubleRaw = fastHexToU64(line.c_str() + 14);
-    num = line.substr(31);
+    expectedFloatRaw = fastHexToU32(line + 5);
+    expectedDoubleRaw = fastHexToU64(line + 14);
+    num = line + 31;
 
-    float floatResult = strtof(num.c_str(), nullptr);
+    float floatResult = LIBC_NAMESPACE::strtof(num, nullptr);
 
-    double doubleResult = strtod(num.c_str(), nullptr);
+    double doubleResult = LIBC_NAMESPACE::strtod(num, nullptr);
 
     uint32_t floatRaw = *(uint32_t *)(&floatResult);
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lntue wrote:

change this to `cpp::bit_cast<uint32_t>(floatResult)`, and similarly for `doubleResult`.

https://github.com/llvm/llvm-project/pull/133978