Changeset 74330e7

Timestamp:

Feb 8, 2020, 10:07:49 AM (5 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

3ecfa13

Parents:

3e274ab

Message:

formatting, add floating-point signal handler to cpp-cc to catch division by 0 in constant-expression evaluations

Files:

• libcfa/src/interpose.cfa (modified) (4 diffs)
• src/main.cc (modified) (5 diffs)

libcfa/src/interpose.cfa

@@ -10 +10 @@
 // Created On       : Wed Mar 29 16:10:31 2017
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Tue Feb  4 11:38:20 2020
-// Update Count     : 161
+// Last Modified On : Sat Feb  8 08:40:34 2020
+// Update Count     : 163
 //
 
@@ -170 +170 @@
 
 static void __cfaabi_backtrace( int start ) {
-        enum {
-                Frames = 50,                                                                    // maximum number of stack frames
-        };
+        enum { Frames = 50, };                                                          // maximum number of stack frames
         int last = kernel_abort_lastframe();                            // skip last N stack frames
 
         void * array[Frames];
         size_t size = backtrace( array, Frames );
-        char ** messages = backtrace_symbols( array, size );
+        char ** messages = backtrace_symbols( array, size ); // does not demangle names
 
         *index( messages[0], '(' ) = '\0';                                      // find executable name
@@ -185 +183 @@
                 char * name = 0p, * offset_begin = 0p, * offset_end = 0p;
 
-                for ( char * p = messages[i]; *p; ++p ) {               // find parantheses and +offset
+                for ( char * p = messages[i]; *p; p += 1 ) {    // find parantheses and +offset
                         //__cfaabi_bits_print_nolock( "X %s\n", p);
                         if ( *p == '(' ) {
@@ -237 +235 @@
         __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
 
-        if ( fmt[strlen( fmt ) - 1] != '\n' ) {                 // add optional newline if missing at the end of the format text
+        if ( fmt[strlen( fmt ) - 1] != '\n' ) {                         // add optional newline if missing at the end of the format text
                 __cfaabi_dbg_write( "\n", 1 );
         }

src/main.cc

@@ -10 +10 @@
 // Created On       : Fri May 15 23:12:02 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Mon Dec 16 17:55:53 2019
-// Update Count     : 627
+// Last Modified On : Sat Feb  8 08:33:50 2020
+// Update Count     : 633
 //
 
@@ -105 +105 @@
 
 static void backtrace( int start ) {                                    // skip first N stack frames
-        enum { Frames = 50 };
+        enum { Frames = 50, };                                                          // maximum number of stack frames
         void * array[Frames];
-        int size = ::backtrace( array, Frames );
+        size_t size = ::backtrace( array, Frames );
         char ** messages = ::backtrace_symbols( array, size ); // does not demangle names
 
@@ -114 +114 @@
 
         // skip last 2 stack frames after main
-        for ( int i = start; i < size - 2 && messages != nullptr; i += 1 ) {
+        for ( unsigned int i = start; i < size - 2 && messages != nullptr; i += 1 ) {
                 char * mangled_name = nullptr, * offset_begin = nullptr, * offset_end = nullptr;
 
@@ -180 +180 @@
 } // sigSegvBusHandler
 
+static void sigFpeHandler( SIGPARMS ) {
+        const char * msg;
+
+        switch ( sfp->si_code ) {
+          case FPE_INTDIV: case FPE_FLTDIV: msg = "divide by zero"; break;
+          case FPE_FLTOVF: msg = "overflow"; break;
+          case FPE_FLTUND: msg = "underflow"; break;
+          case FPE_FLTRES: msg = "inexact result"; break;
+          case FPE_FLTINV: msg = "invalid operation"; break;
+          default: msg = "unknown";
+        } // choose
+        cerr << "Computation error " << msg << " at location " << sfp->si_addr << endl
+                 << "Possible cause is constant-expression evaluation invalid." << endl;
+        backtrace( 2 );                                                                         // skip first 2 stack frames
+        abort();                                                                                        // cause core dump for debugging
+} // sigFpeHandler
+
 static void sigAbortHandler( SIGPARMS ) {
         backtrace( 6 );                                                                         // skip first 6 stack frames
@@ -193 +210 @@
         Signal( SIGSEGV, sigSegvBusHandler, SA_SIGINFO );
         Signal( SIGBUS, sigSegvBusHandler, SA_SIGINFO );
+        Signal( SIGFPE, sigFpeHandler, SA_SIGINFO );
         Signal( SIGABRT, sigAbortHandler, SA_SIGINFO );