Fix parsing of subnormal Real values (#9696)

- Fix parsing of Real values between DBL_TRUE_MIN and DBL_MIN.
OpenModelica · Nov 14, 2022 · 65de200 · 65de200
1 parent d06b6c8
commit 65de200
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Showing 4 changed files with 30 additions and 2 deletions.
diff --git a/OMCompiler/Parser/Modelica.g b/OMCompiler/Parser/Modelica.g
@@ -1762,7 +1762,9 @@ primary returns [void* ast]
       if (errno == 0) // restore errno
         errno = errno_saved;
       if (!(*endptr == 0 && errno_local == 0)) {
-        if (*endptr == 0 && errno_local == ERANGE && fabs(d) == HUGE_VAL) { // overflow is an error
+        if (*endptr == 0 && !(d == 0 || fabs(d) > DBL_MIN)) { // ignore errors for subnormal values
+          $ast = Absyn__REAL(mmc_mk_scon(chars));
+        } else if (*endptr == 0 && errno_local == ERANGE && fabs(d) == HUGE_VAL) { // overflow is an error
           c_add_source_message(NULL, 2, ErrorType_syntax, ErrorLevel_error, "Overflow: \%s cannot be represented by a double on this machine", (const char **)&chars, 1, $start->line, $start->charPosition+1, LT(1)->line, LT(1)->charPosition+1, ModelicaParser_readonly, ModelicaParser_filename_C_testsuiteFriendly);
           $ast = Absyn__REAL(mmc_mk_scon(chars));
           ModelicaParser_lexerError = ANTLR3_TRUE;

diff --git a/OMCompiler/SimulationRuntime/c/meta/meta_modelica_builtin.c b/OMCompiler/SimulationRuntime/c/meta/meta_modelica_builtin.c
@@ -101,7 +101,7 @@ modelica_real nobox_stringReal(threadData_t *threadData,metamodelica_string s)
   MMC_CHECK_STRING(s);
   errno = 0;
   res = om_strtod(str,&endptr);
-  if (errno != 0 || str == endptr)
+  if ((errno != 0 && (res == 0 || res > DBL_MIN)) || str == endptr)
     MMC_THROW_INTERNAL();
   if (*endptr != '\0')
     MMC_THROW_INTERNAL();

diff --git a/testsuite/openmodelica/parser/Makefile b/testsuite/openmodelica/parser/Makefile
@@ -43,6 +43,7 @@ ParseString.mos \
 PureImpure.mo \
 PureImpure2.mo \
 PureImpure3.mo \
+RealLiterals1.mo \
 RealOpLexerModelica.mo \
 Redeclare.mos \
 ReloadClass.mos \

diff --git a/testsuite/openmodelica/parser/RealLiterals1.mo b/testsuite/openmodelica/parser/RealLiterals1.mo
@@ -0,0 +1,25 @@
+// name: RealLiterals1
+// keywords:
+// status: correct
+// cflags: -d=-newInst
+//
+//
+
+model RealLiterals1
+  Real x_min1 = -4.940656458412465e-324;
+  Real x_min2 = 4.940656458412465e-324;
+  Real x_underflow1 = -4.9e-325;
+  Real x_underflow2 = 4.9e-325;
+end RealLiterals1;
+
+// Result:
+// [openmodelica/parser/RealLiterals1.mo:11:24-11:32:writable] Warning: Underflow: 4.9e-325 cannot be represented by a double on this machine. It will be converted to 0.0.
+// [openmodelica/parser/RealLiterals1.mo:12:23-12:31:writable] Warning: Underflow: 4.9e-325 cannot be represented by a double on this machine. It will be converted to 0.0.
+//
+// class RealLiterals1
+//   Real x_min1 = -4.940656458412465e-324;
+//   Real x_min2 = 4.940656458412465e-324;
+//   Real x_underflow1 = -0.0;
+//   Real x_underflow2 = 0.0;
+// end RealLiterals1;
+// endResult