goto-cc: Replace assert(...) by macros from invariant.h

While new/modified code shouldn't use assert(...) anyway, we had several
existing uses of assert. Once we remove nonstd/optional.h, we will no
longer implicitly include cassert, implying that a lot of #include
<cassert> changes will be necessary. Instead of adding these, go all the
way and fix the undesired uses of assert.

Author: tautschnig

src/goto-cc/as86_cmdline.cpp

@@ -11,10 +11,11 @@ Author: Michael Tautschnig
 
 #include "as86_cmdline.h"
 
-#include <iostream>
-
+#include <util/invariant.h>
 #include <util/prefix.h>
 
+#include <iostream>
+
 // non-as86 options
 const char *goto_as86_options_with_argument[]=
 {
@@ -56,7 +57,7 @@ const char *as86_options_with_argument[]=
 
 bool as86_cmdlinet::parse(int argc, const char **argv)
 {
-  assert(argc>0);
+  PRECONDITION(argc > 0);
   add_arg(argv[0]);
 
   for(int i=1; i<argc; i++)

src/goto-cc/as_cmdline.cpp

@@ -11,10 +11,11 @@ Author: Michael Tautschnig
 
 #include "as_cmdline.h"
 
-#include <iostream>
-
+#include <util/invariant.h>
 #include <util/prefix.h>
 
+#include <iostream>
+
 // non-as options
 const char *goto_as_options_with_argument[]=
 {
@@ -78,7 +79,7 @@ const char *as_options_with_argument[]=
 
 bool as_cmdlinet::parse(int argc, const char **argv)
 {
-  assert(argc>0);
+  PRECONDITION(argc > 0);
   add_arg(argv[0]);
 
   for(int i=1; i<argc; i++)

src/goto-cc/as_mode.cpp

@@ -201,7 +201,7 @@ int as_modet::doit()
       {
         if(outputs>0)
         {
-          assert(!dest.empty());
+          PRECONDITION(!dest.empty());
           compiler.add_input_file(dest);
           os.close();
         }
@@ -230,7 +230,7 @@ int as_modet::doit()
 
     if(outputs>0)
     {
-      assert(!dest.empty());
+      PRECONDITION(!dest.empty());
       compiler.add_input_file(dest);
     }
     else
@@ -260,7 +260,7 @@ int as_modet::doit()
 /// run as or as86 with original command line
 int as_modet::run_as()
 {
-  assert(!cmdline.parsed_argv.empty());
+  PRECONDITION(!cmdline.parsed_argv.empty());
 
   // build new argv
   std::vector<std::string> new_argv;

src/goto-cc/bcc_cmdline.cpp

@@ -11,10 +11,11 @@ Author: Michael Tautschnig
 
 #include "bcc_cmdline.h"
 
-#include <iostream>
-
+#include <util/invariant.h>
 #include <util/prefix.h>
 
+#include <iostream>
+
 // non-bcc options
 const char *goto_bcc_options_with_argument[]=
 {
@@ -68,7 +69,7 @@ const char *bcc_options_with_argument[]=
 
 bool bcc_cmdlinet::parse(int argc, const char **argv)
 {
-  assert(argc>0);
+  PRECONDITION(argc > 0);
   add_arg(argv[0]);
 
   for(int i=1; i<argc; i++)

src/goto-cc/gcc_cmdline.cpp

@@ -11,6 +11,7 @@ Author: CM Wintersteiger, 2006
 
 #include "gcc_cmdline.h"
 
+#include <util/invariant.h>
 #include <util/prefix.h>
 
 #include <cstring>
@@ -228,7 +229,7 @@ const char *gcc_options_without_argument[]=
 /// \return none
 bool gcc_cmdlinet::parse(int argc, const char **argv)
 {
-  assert(argc>0);
+  PRECONDITION(argc > 0);
   add_arg(argv[0]);
 
   argst current_args;
@@ -447,8 +448,8 @@ bool gcc_cmdlinet::parse_arguments(
 void gcc_cmdlinet::parse_specs_line(const std::string &line, bool in_spec_file)
 {
   // initial whitespace has been stripped
-  assert(!line.empty());
-  assert(line[0]!=' ' && line[0]!='\t');
+  PRECONDITION(!line.empty());
+  PRECONDITION(line[0] != ' ' && line[0] != '\t');
 
   argst args_from_specs;
 

src/goto-cc/ld_cmdline.cpp

@@ -11,10 +11,11 @@ Author: Daniel Kroening, 2013
 
 #include "ld_cmdline.h"
 
-#include <iostream>
-
+#include <util/invariant.h>
 #include <util/prefix.h>
 
+#include <iostream>
+
 // clang-format off
 const char *goto_ld_options_with_argument[]=
 {
@@ -253,7 +254,7 @@ const char *ld_options_without_argument[]=
 /// \return none
 bool ld_cmdlinet::parse(int argc, const char **argv)
 {
-  assert(argc>0);
+  PRECONDITION(argc > 0);
   add_arg(argv[0]);
 
   for(int i=1; i<argc; i++)