lang-options.h, decl2.c: Add -fno-enforce-eh-specs.

        * lang-options.h, decl2.c: Add -fno-enforce-eh-specs.
        * cp-tree.h: Declare flag_enforce_eh_specs.
        * decl.c (store_parm_decls, finish_function): Check it.

        C library functions don't throw.
        * Makefile.in (cfns.h): New target.
        (except.o): Depend on it.
        * Make-lang.in (cc1plus): Depend on cfns.gperf.
        * cfns.gperf: New file.
        * cfns.h: Generated.
        * except.c: Include it.
        (nothrow_libfn_p): New fn.
        * decl.c (grokfndecl): Use it.
        * cp-tree.h: Declare it.

From-SVN: r32469

gcc/cp/ChangeLog

 2000-03-10  Jason Merrill  <jason@casey.cygnus.com>
 
+	* lang-options.h, decl2.c: Add -fno-enforce-eh-specs.
+	* cp-tree.h: Declare flag_enforce_eh_specs.
+	* decl.c (store_parm_decls, finish_function): Check it.
+
+	C library functions don't throw.
+	* Makefile.in (cfns.h): New target.
+	(except.o): Depend on it.
+	* Make-lang.in (cc1plus): Depend on cfns.gperf.
+	* cfns.gperf: New file.
+	* cfns.h: Generated.
+	* except.c: Include it.
+	(nothrow_libfn_p): New fn.
+	* decl.c (grokfndecl): Use it.
+	* cp-tree.h: Declare it.
+	
 	* decl.c (push_overloaded_decl_1, auto_function, 
 	define_function): Lose.
 	(build_library_fn_1): New static fn.

gcc/cp/Make-lang.in

@@ -123,7 +123,7 @@ CXX_SRCS = $(srcdir)/cp/call.c $(srcdir)/cp/class.c $(srcdir)/cp/cp-tree.def \
 
 cc1plus$(exeext): $(P) $(CXX_SRCS) $(LIBDEPS) stamp-objlist c-common.o \
         c-pragma.o $(srcdir)/cp/cp-tree.h $(srcdir)/cp/cp-tree.def \
-	$(srcdir)/cp/gxx.gperf hash.o
+	$(srcdir)/cp/gxx.gperf $(srcdir)/cp/cfns.gperf hash.o
 	cd cp; $(MAKE) $(FLAGS_TO_PASS) $(CXX_FLAGS_TO_PASS) ../cc1plus$(exeext)
 #
 # Build hooks:

gcc/cp/Makefile.in

@@ -242,6 +242,10 @@ $(srcdir)/hash.h: $(srcdir)/gxx.gperf
 	echo "	ftp://sourceware.cygnus.com/pub/egcs/infrastructure/gperf*" >&2 ; \
 	exit 1 )
 
+$(srcdir)/cfns.h: $(srcdir)/cfns.gperf
+	gperf -o -C -E -k '1-6,$$' -j1 -D -N 'libc_name_p' \
+		$(srcdir)/cfns.gperf > $(srcdir)/cfns.h
+
 spew.o : spew.c $(CXX_TREE_H) $(PARSE_H) $(srcdir)/../flags.h \
   lex.h $(srcdir)/../toplev.h
 lex.o : lex.c $(CXX_TREE_H) \
@@ -283,7 +287,7 @@ ptree.o : ptree.c $(CXX_TREE_H) $(srcdir)/../system.h
 rtti.o : rtti.c $(CXX_TREE_H) $(srcdir)/../flags.h \
   $(srcdir)/../toplev.h
 except.o : except.c $(CXX_TREE_H) $(srcdir)/../flags.h $(RTL_H) \
-  $(srcdir)/../except.h $(srcdir)/../toplev.h
+  $(srcdir)/../except.h $(srcdir)/../toplev.h cfns.h
 expr.o : expr.c $(CXX_TREE_H) $(RTL_H) $(srcdir)/../flags.h \
   $(EXPR_H) $(srcdir)/../toplev.h $(srcdir)/../except.h
 xref.o : xref.c $(CXX_TREE_H) $(srcdir)/../input.h \

gcc/cp/cfns.gperf

+# The standard C library functions, for feeding to gperf; the result is used
+# by nothrow_libfn_p.
+#
+#   [lib.res.on.exception.handling]: None of the functions from the
+#   Standard C library shall report an error by throwing an
+#   exception, unless it calls a program-supplied function that
+#   throws an exception.
+#
+# bsearch and qsort are commented out because they can call such functions.
+#
+abort
+abs
+acos
+asctime
+asin
+atan
+atan2
+atexit
+atof
+atoi
+atol
+#bsearch
+btowc
+calloc
+ceil
+clearerr
+clock
+cos
+cosh
+ctime
+difftime
+div
+exit
+exp
+fabs
+fclose
+feof
+ferror
+fflush
+fgetc
+fgetpos
+fgets
+fgetwc
+fgetws
+floor
+fmod
+fopen
+fprintf
+fputc
+fputs
+fputwc
+fputws
+fread
+free
+freopen
+frexp
+fscanf
+fseek
+fsetpos
+ftell
+fwide
+fwprintf
+fwrite
+fwscanf
+getc
+getchar
+getenv
+gets
+getwc
+getwchar
+gmtime
+isalnum
+isalpha
+iscntrl
+isdigit
+isgraph
+islower
+isprint
+ispunct
+isspace
+isupper
+iswalnum
+iswalpha
+iswcntrl
+iswctype
+iswdigit
+iswgraph
+iswlower
+iswprint
+iswpunct
+iswspace
+iswupper
+iswxdigit
+isxdigit
+labs
+ldexp
+ldiv
+localeconv
+localtime
+log
+log10
+longjmp
+malloc
+mblen
+mbrlen
+mbrtowc
+mbsinit
+mbsrtowcs
+mbstowcs
+mbtowc
+memchr
+memcmp
+memcpy
+memmove
+memset
+mktime
+modf
+perror
+pow
+printf
+putc
+putchar
+puts
+putwc
+putwchar
+#qsort
+raise
+rand
+realloc
+remove
+rename
+rewind
+scanf
+setbuf
+setlocale
+setvbuf
+signal
+sin
+sinh
+sprintf
+sqrt
+srand
+sscanf
+strcat
+strchr
+strcmp
+strcoll
+strcpy
+strcspn
+strerror
+strftime
+strlen
+strncat
+strncmp
+strncpy
+strpbrk
+strrchr
+strspn
+strstr
+strtod
+strtok
+strtol
+strtoul
+strxfrm
+swprintf
+swscanf
+system
+tan
+tanh
+time
+tmpfile
+tmpnam
+tolower
+toupper
+towctrans
+towlower
+towupper
+ungetc
+ungetwc
+vfprintf
+vfwprintf
+vprintf
+vsprintf
+vswprintf
+vwprintf
+wcrtomb
+wcscat
+wcschr
+wcscmp
+wcscoll
+wcscpy
+wcscspn
+wcsftime
+wcslen
+wcsncat
+wcsncmp
+wcsncpy
+wcspbrk
+wcsrchr
+wcsrtombs
+wcsspn
+wcsstr
+wcstod
+wcstok
+wcstol
+wcstombs
+wcstoul
+wcsxfrm
+wctob
+wctomb
+wctrans
+wctype
+wmemchr
+wmemcmp
+wmemcpy
+wmemmove
+wmemset
+wprintf
+wscanf

gcc/cp/cp-tree.h

@@ -1149,6 +1149,12 @@ extern int flag_vtable_gc;
    The value of this flag is ignored if -pedantic is specified.  */
 extern int flag_permissive;
 
+/* Nonzero means to implement standard semantics for exception
+   specifications, calling unexpected if an exception is thrown that
+   doesn't match the specification.  Zero means to treat them as
+   assertions and optimize accordingly, but not check them.  */
+extern int flag_enforce_eh_specs;
+
 /* Nonzero if we want to obey access control semantics.  */
 
 extern int flag_access_control;
@@ -3922,6 +3928,7 @@ extern void expand_end_eh_spec		        PARAMS ((tree, tree));
 extern void expand_exception_blocks		PARAMS ((void));
 extern tree build_throw				PARAMS ((tree));
 extern void mark_all_runtime_matches            PARAMS ((void));
+extern int nothrow_libfn_p			PARAMS ((tree));
 
 /* in expr.c */
 extern void init_cplus_expand			PARAMS ((void));

gcc/cp/decl.c

@@ -8668,6 +8668,9 @@ grokfndecl (ctype, type, declarator, orig_declarator, virtualp, flags, quals,
        tentative.  error_mark_node is replaced later with the BLOCK.  */
     DECL_INITIAL (decl) = error_mark_node;
 
+  if (nothrow_libfn_p (decl))
+    TREE_NOTHROW (decl) = 1;
+
   /* Caller will do the rest of this.  */
   if (check < 0)
     return decl;
@@ -13563,6 +13566,7 @@ store_parm_decls ()
 
   /* Do the starting of the exception specifications, if we have any.  */
   if (flag_exceptions && !processing_template_decl
+      && flag_enforce_eh_specs
       && building_stmt_tree ()
       && TYPE_RAISES_EXCEPTIONS (TREE_TYPE (current_function_decl)))
     current_eh_spec_try_block = expand_start_eh_spec ();
@@ -13840,6 +13844,7 @@ finish_function (lineno, flags)
 
       /* Finish dealing with exception specifiers.  */
       if (flag_exceptions && !processing_template_decl
+	  && flag_enforce_eh_specs
 	  && TYPE_RAISES_EXCEPTIONS (TREE_TYPE (current_function_decl)))
 	expand_end_eh_spec (TYPE_RAISES_EXCEPTIONS
 			    (TREE_TYPE (current_function_decl)),

gcc/cp/decl2.c

@@ -490,6 +490,13 @@ int flag_vtable_gc;
 
 int flag_permissive;
 
+/* Nonzero means to implement standard semantics for exception
+   specifications, calling unexpected if an exception is thrown that
+   doesn't match the specification.  Zero means to treat them as
+   assertions and optimize accordingly, but not check them.  */
+
+int flag_enforce_eh_specs = 1;
+
 /* If this variable is defined to a non-NULL value, it will be called
    after the file has been completely parsed.  */
 
@@ -524,6 +531,7 @@ lang_f_options[] =
   {"default-inline", &flag_default_inline, 1},
   {"dollars-in-identifiers", &dollars_in_ident, 1},
   {"elide-constructors", &flag_elide_constructors, 1},
+  {"enforce-eh-specs", &flag_enforce_eh_specs, 1},
   {"external-templates", &flag_external_templates, 1},
   {"for-scope", &flag_new_for_scope, 2},
   {"gnu-keywords", &flag_no_gnu_keywords, 0},

gcc/cp/except.c

@@ -1027,3 +1027,30 @@ complete_ptr_ref_or_void_ptr_p (type, from)
   return 1;
 }
 
+/* Returns nonzero if FN is a declaration of a standard C library
+   function which is known not to throw.
+
+   [lib.res.on.exception.handling]: None of the functions from the
+   Standard C library shall report an error by throwing an
+   exception, unless it calls a program-supplied function that
+   throws an exception.  */
+
+#include "cfns.h"
+
+int
+nothrow_libfn_p (fn)
+     tree fn;
+{
+  tree id;
+
+  if (TREE_PUBLIC (fn)
+      && DECL_EXTERNAL (fn)
+      && DECL_LANGUAGE (fn) == lang_c)
+    /* OK */;
+  else
+    /* Can't be a C library function.  */
+    return 0;
+
+  id = DECL_ASSEMBLER_NAME (fn);
+  return !!libc_name_p (IDENTIFIER_POINTER (id), IDENTIFIER_LENGTH (id));
+}

gcc/cp/lang-options.h

@@ -45,6 +45,8 @@ DEFINE_LANG_NAME ("C++")
   { "-fno-rtti", "Do not generate run time type descriptor information" },
   { "-felide-constructors", "" },
   { "-fno-elide-constructors", "" },
+  { "-fenforce-eh-specs", "" },
+  { "-fno-enforce-eh-specs", "Do not generate code to check exception specifications" },
   { "-fenum-int-equiv", "" },
   { "-fno-enum-int-equiv", "" },
   { "-fexternal-templates", "" },