PCG32 patch for Emacs

emacs-pcg32.patch

Switch to a permuted congruential generator

Rather than try to detect and use whatever PRNG happens to be a
available on the system, just implement a PRNG in Emacs. This generator
is stronger, faster, and more reliable than any system-provided PRNG.
This implementation also works on all platforms supported by Emacs.

This is a mixture of GPL-licensed code and my own. To the extent that it
is possible, I hereby release my changes into the public domain.
---
 admin/CPP-DEFINES         |   2 -
 lib/gnulib.mk.in          |  15 ---
 lib/stdlib.in.h           | 269 ----------------------------------------------
 m4/stdlib_h.m4            |   6 --
 msdos/autogen/Makefile.in |  10 --
 msdos/autogen/config.in   |   6 --
 msdos/sedlibmk.inp        |   2 -
 src/conf_post.h           |   8 --
 src/sysdep.c              |  93 ++++++----------
 9 files changed, 31 insertions(+), 380 deletions(-)

--- a/admin/CPP-DEFINES
+++ b/admin/CPP-DEFINES
@@ -201,7 +201,6 @@
 HAVE_LIBXMU
 HAVE_LOCALTIME_R
 HAVE_LOCAL_SOCKETS
-HAVE_LRAND48
 HAVE_LSTAT
 HAVE_LUTIMES
 HAVE_M17N_FLT
@@ -239,7 +238,6 @@
 HAVE_PTYS
 HAVE_PTY_H
 HAVE_PWD_H
-HAVE_RANDOM
 HAVE_READLINK
 HAVE_READLINKAT
 HAVE_RECVFROM
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@@ -396,8 +396,6 @@
 GNULIB_PWRITE = @GNULIB_PWRITE@
 GNULIB_QSORT_R = @GNULIB_QSORT_R@
 GNULIB_RAISE = @GNULIB_RAISE@
-GNULIB_RANDOM = @GNULIB_RANDOM@
-GNULIB_RANDOM_R = @GNULIB_RANDOM_R@
 GNULIB_RAWMEMCHR = @GNULIB_RAWMEMCHR@
 GNULIB_READ = @GNULIB_READ@
 GNULIB_READDIR = @GNULIB_READDIR@
@@ -619,9 +617,6 @@
 HAVE_PWRITE = @HAVE_PWRITE@
 HAVE_QSORT_R = @HAVE_QSORT_R@
 HAVE_RAISE = @HAVE_RAISE@
-HAVE_RANDOM = @HAVE_RANDOM@
-HAVE_RANDOM_H = @HAVE_RANDOM_H@
-HAVE_RANDOM_R = @HAVE_RANDOM_R@
 HAVE_RAWMEMCHR = @HAVE_RAWMEMCHR@
 HAVE_READDIR = @HAVE_READDIR@
 HAVE_READLINK = @HAVE_READLINK@
@@ -656,7 +651,6 @@
 HAVE_STRTOLD = @HAVE_STRTOLD@
 HAVE_STRTOLL = @HAVE_STRTOLL@
 HAVE_STRTOULL = @HAVE_STRTOULL@
-HAVE_STRUCT_RANDOM_DATA = @HAVE_STRUCT_RANDOM_DATA@
 HAVE_STRUCT_SIGACTION_SA_SIGACTION = @HAVE_STRUCT_SIGACTION_SA_SIGACTION@
 HAVE_STRUCT_TIMEVAL = @HAVE_STRUCT_TIMEVAL@
 HAVE_STRVERSCMP = @HAVE_STRVERSCMP@
@@ -922,8 +916,6 @@
 REPLACE_PWRITE = @REPLACE_PWRITE@
 REPLACE_QSORT_R = @REPLACE_QSORT_R@
 REPLACE_RAISE = @REPLACE_RAISE@
-REPLACE_RANDOM = @REPLACE_RANDOM@
-REPLACE_RANDOM_R = @REPLACE_RANDOM_R@
 REPLACE_READ = @REPLACE_READ@
 REPLACE_READLINK = @REPLACE_READLINK@
 REPLACE_READLINKAT = @REPLACE_READLINKAT@
@@ -2659,8 +2651,6 @@
 	      -e 's/@''GNULIB_PTSNAME_R''@/$(GNULIB_PTSNAME_R)/g' \
 	      -e 's/@''GNULIB_PUTENV''@/$(GNULIB_PUTENV)/g' \
 	      -e 's/@''GNULIB_QSORT_R''@/$(GNULIB_QSORT_R)/g' \
-	      -e 's/@''GNULIB_RANDOM''@/$(GNULIB_RANDOM)/g' \
-	      -e 's/@''GNULIB_RANDOM_R''@/$(GNULIB_RANDOM_R)/g' \
 	      -e 's/@''GNULIB_REALLOC_POSIX''@/$(GNULIB_REALLOC_POSIX)/g' \
 	      -e 's/@''GNULIB_REALLOCARRAY''@/$(GNULIB_REALLOCARRAY)/g' \
 	      -e 's/@''GNULIB_REALPATH''@/$(GNULIB_REALPATH)/g' \
@@ -2694,9 +2684,6 @@
 	      -e 's|@''HAVE_PTSNAME''@|$(HAVE_PTSNAME)|g' \
 	      -e 's|@''HAVE_PTSNAME_R''@|$(HAVE_PTSNAME_R)|g' \
 	      -e 's|@''HAVE_QSORT_R''@|$(HAVE_QSORT_R)|g' \
-	      -e 's|@''HAVE_RANDOM''@|$(HAVE_RANDOM)|g' \
-	      -e 's|@''HAVE_RANDOM_H''@|$(HAVE_RANDOM_H)|g' \
-	      -e 's|@''HAVE_RANDOM_R''@|$(HAVE_RANDOM_R)|g' \
 	      -e 's|@''HAVE_REALLOCARRAY''@|$(HAVE_REALLOCARRAY)|g' \
 	      -e 's|@''HAVE_REALPATH''@|$(HAVE_REALPATH)|g' \
 	      -e 's|@''HAVE_RPMATCH''@|$(HAVE_RPMATCH)|g' \
@@ -2722,8 +2709,6 @@
 	      -e 's|@''REPLACE_PTSNAME_R''@|$(REPLACE_PTSNAME_R)|g' \
 	      -e 's|@''REPLACE_PUTENV''@|$(REPLACE_PUTENV)|g' \
 	      -e 's|@''REPLACE_QSORT_R''@|$(REPLACE_QSORT_R)|g' \
-	      -e 's|@''REPLACE_RANDOM''@|$(REPLACE_RANDOM)|g' \
-	      -e 's|@''REPLACE_RANDOM_R''@|$(REPLACE_RANDOM_R)|g' \
 	      -e 's|@''REPLACE_REALLOC''@|$(REPLACE_REALLOC)|g' \
 	      -e 's|@''REPLACE_REALPATH''@|$(REPLACE_REALPATH)|g' \
 	      -e 's|@''REPLACE_SETENV''@|$(REPLACE_SETENV)|g' \
--- a/lib/stdlib.in.h
+++ b/lib/stdlib.in.h
@@ -58,38 +58,6 @@
 # include <io.h>
 #endif
 
-#if @GNULIB_RANDOM_R@
-
-/* OSF/1 5.1 declares 'struct random_data' in <random.h>, which is included
-   from <stdlib.h> if _REENTRANT is defined.  Include it whenever we need
-   'struct random_data'.  */
-# if @HAVE_RANDOM_H@
-#  include <random.h>
-# endif
-
-# if !@HAVE_STRUCT_RANDOM_DATA@ || @REPLACE_RANDOM_R@ || !@HAVE_RANDOM_R@
-#  include <stdint.h>
-# endif
-
-# if !@HAVE_STRUCT_RANDOM_DATA@
-/* Define 'struct random_data'.
-   But allow multiple gnulib generated <stdlib.h> replacements to coexist.  */
-#  if !GNULIB_defined_struct_random_data
-struct random_data
-{
-  int32_t *fptr;                /* Front pointer.  */
-  int32_t *rptr;                /* Rear pointer.  */
-  int32_t *state;               /* Array of state values.  */
-  int rand_type;                /* Type of random number generator.  */
-  int rand_deg;                 /* Degree of random number generator.  */
-  int rand_sep;                 /* Distance between front and rear.  */
-  int32_t *end_ptr;             /* Pointer behind state table.  */
-};
-#   define GNULIB_defined_struct_random_data 1
-#  endif
-# endif
-#endif
-
 #if (@GNULIB_MKSTEMP@ || @GNULIB_MKSTEMPS@ || @GNULIB_MKOSTEMP@ || @GNULIB_MKOSTEMPS@ || @GNULIB_GETSUBOPT@ || defined GNULIB_POSIXCHECK) && ! defined __GLIBC__ && !(defined _WIN32 && ! defined __CYGWIN__)
 /* On Mac OS X 10.3, only <unistd.h> declares mkstemp.  */
 /* On Mac OS X 10.5, only <unistd.h> declares mkstemps.  */
@@ -590,243 +558,6 @@
 # endif
 #endif
 
-
-#if @GNULIB_RANDOM_R@
-# if !@HAVE_RANDOM_R@
-#  ifndef RAND_MAX
-#   define RAND_MAX 2147483647
-#  endif
-# endif
-#endif
-
-
-#if @GNULIB_RANDOM@
-# if @REPLACE_RANDOM@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef random
-#   define random rpl_random
-#  endif
-_GL_FUNCDECL_RPL (random, long, (void));
-_GL_CXXALIAS_RPL (random, long, (void));
-# else
-#  if !@HAVE_RANDOM@
-_GL_FUNCDECL_SYS (random, long, (void));
-#  endif
-/* Need to cast, because on Haiku, the return type is
-                               int.  */
-_GL_CXXALIAS_SYS_CAST (random, long, (void));
-# endif
-_GL_CXXALIASWARN (random);
-#elif defined GNULIB_POSIXCHECK
-# undef random
-# if HAVE_RAW_DECL_RANDOM
-_GL_WARN_ON_USE (random, "random is unportable - "
-                 "use gnulib module random for portability");
-# endif
-#endif
-
-#if @GNULIB_RANDOM@
-# if @REPLACE_RANDOM@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef srandom
-#   define srandom rpl_srandom
-#  endif
-_GL_FUNCDECL_RPL (srandom, void, (unsigned int seed));
-_GL_CXXALIAS_RPL (srandom, void, (unsigned int seed));
-# else
-#  if !@HAVE_RANDOM@
-_GL_FUNCDECL_SYS (srandom, void, (unsigned int seed));
-#  endif
-/* Need to cast, because on FreeBSD, the first parameter is
-                                       unsigned long seed.  */
-_GL_CXXALIAS_SYS_CAST (srandom, void, (unsigned int seed));
-# endif
-_GL_CXXALIASWARN (srandom);
-#elif defined GNULIB_POSIXCHECK
-# undef srandom
-# if HAVE_RAW_DECL_SRANDOM
-_GL_WARN_ON_USE (srandom, "srandom is unportable - "
-                 "use gnulib module random for portability");
-# endif
-#endif
-
-#if @GNULIB_RANDOM@
-# if @REPLACE_INITSTATE@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef initstate
-#   define initstate rpl_initstate
-#  endif
-_GL_FUNCDECL_RPL (initstate, char *,
-                  (unsigned int seed, char *buf, size_t buf_size)
-                  _GL_ARG_NONNULL ((2)));
-_GL_CXXALIAS_RPL (initstate, char *,
-                  (unsigned int seed, char *buf, size_t buf_size));
-# else
-#  if !@HAVE_INITSTATE@ || !@HAVE_DECL_INITSTATE@
-_GL_FUNCDECL_SYS (initstate, char *,
-                  (unsigned int seed, char *buf, size_t buf_size)
-                  _GL_ARG_NONNULL ((2)));
-#  endif
-/* Need to cast, because on FreeBSD, the first parameter is
-                        unsigned long seed.  */
-_GL_CXXALIAS_SYS_CAST (initstate, char *,
-                       (unsigned int seed, char *buf, size_t buf_size));
-# endif
-_GL_CXXALIASWARN (initstate);
-#elif defined GNULIB_POSIXCHECK
-# undef initstate
-# if HAVE_RAW_DECL_INITSTATE
-_GL_WARN_ON_USE (initstate, "initstate is unportable - "
-                 "use gnulib module random for portability");
-# endif
-#endif
-
-#if @GNULIB_RANDOM@
-# if @REPLACE_SETSTATE@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef setstate
-#   define setstate rpl_setstate
-#  endif
-_GL_FUNCDECL_RPL (setstate, char *, (char *arg_state) _GL_ARG_NONNULL ((1)));
-_GL_CXXALIAS_RPL (setstate, char *, (char *arg_state));
-# else
-#  if !@HAVE_SETSTATE@ || !@HAVE_DECL_SETSTATE@
-_GL_FUNCDECL_SYS (setstate, char *, (char *arg_state) _GL_ARG_NONNULL ((1)));
-#  endif
-/* Need to cast, because on Mac OS X 10.13, HP-UX, Solaris the first parameter
-   is                                     const char *arg_state.  */
-_GL_CXXALIAS_SYS_CAST (setstate, char *, (char *arg_state));
-# endif
-_GL_CXXALIASWARN (setstate);
-#elif defined GNULIB_POSIXCHECK
-# undef setstate
-# if HAVE_RAW_DECL_SETSTATE
-_GL_WARN_ON_USE (setstate, "setstate is unportable - "
-                 "use gnulib module random for portability");
-# endif
-#endif
-
-
-#if @GNULIB_RANDOM_R@
-# if @REPLACE_RANDOM_R@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef random_r
-#   define random_r rpl_random_r
-#  endif
-_GL_FUNCDECL_RPL (random_r, int, (struct random_data *buf, int32_t *result)
-                                 _GL_ARG_NONNULL ((1, 2)));
-_GL_CXXALIAS_RPL (random_r, int, (struct random_data *buf, int32_t *result));
-# else
-#  if !@HAVE_RANDOM_R@
-_GL_FUNCDECL_SYS (random_r, int, (struct random_data *buf, int32_t *result)
-                                 _GL_ARG_NONNULL ((1, 2)));
-#  endif
-_GL_CXXALIAS_SYS (random_r, int, (struct random_data *buf, int32_t *result));
-# endif
-_GL_CXXALIASWARN (random_r);
-#elif defined GNULIB_POSIXCHECK
-# undef random_r
-# if HAVE_RAW_DECL_RANDOM_R
-_GL_WARN_ON_USE (random_r, "random_r is unportable - "
-                 "use gnulib module random_r for portability");
-# endif
-#endif
-
-#if @GNULIB_RANDOM_R@
-# if @REPLACE_RANDOM_R@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef srandom_r
-#   define srandom_r rpl_srandom_r
-#  endif
-_GL_FUNCDECL_RPL (srandom_r, int,
-                  (unsigned int seed, struct random_data *rand_state)
-                  _GL_ARG_NONNULL ((2)));
-_GL_CXXALIAS_RPL (srandom_r, int,
-                  (unsigned int seed, struct random_data *rand_state));
-# else
-#  if !@HAVE_RANDOM_R@
-_GL_FUNCDECL_SYS (srandom_r, int,
-                  (unsigned int seed, struct random_data *rand_state)
-                  _GL_ARG_NONNULL ((2)));
-#  endif
-_GL_CXXALIAS_SYS (srandom_r, int,
-                  (unsigned int seed, struct random_data *rand_state));
-# endif
-_GL_CXXALIASWARN (srandom_r);
-#elif defined GNULIB_POSIXCHECK
-# undef srandom_r
-# if HAVE_RAW_DECL_SRANDOM_R
-_GL_WARN_ON_USE (srandom_r, "srandom_r is unportable - "
-                 "use gnulib module random_r for portability");
-# endif
-#endif
-
-#if @GNULIB_RANDOM_R@
-# if @REPLACE_RANDOM_R@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef initstate_r
-#   define initstate_r rpl_initstate_r
-#  endif
-_GL_FUNCDECL_RPL (initstate_r, int,
-                  (unsigned int seed, char *buf, size_t buf_size,
-                   struct random_data *rand_state)
-                  _GL_ARG_NONNULL ((2, 4)));
-_GL_CXXALIAS_RPL (initstate_r, int,
-                  (unsigned int seed, char *buf, size_t buf_size,
-                   struct random_data *rand_state));
-# else
-#  if !@HAVE_RANDOM_R@
-_GL_FUNCDECL_SYS (initstate_r, int,
-                  (unsigned int seed, char *buf, size_t buf_size,
-                   struct random_data *rand_state)
-                  _GL_ARG_NONNULL ((2, 4)));
-#  endif
-/* Need to cast, because on Haiku, the third parameter is
-                                                     unsigned long buf_size.  */
-_GL_CXXALIAS_SYS_CAST (initstate_r, int,
-                       (unsigned int seed, char *buf, size_t buf_size,
-                        struct random_data *rand_state));
-# endif
-_GL_CXXALIASWARN (initstate_r);
-#elif defined GNULIB_POSIXCHECK
-# undef initstate_r
-# if HAVE_RAW_DECL_INITSTATE_R
-_GL_WARN_ON_USE (initstate_r, "initstate_r is unportable - "
-                 "use gnulib module random_r for portability");
-# endif
-#endif
-
-#if @GNULIB_RANDOM_R@
-# if @REPLACE_RANDOM_R@
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef setstate_r
-#   define setstate_r rpl_setstate_r
-#  endif
-_GL_FUNCDECL_RPL (setstate_r, int,
-                  (char *arg_state, struct random_data *rand_state)
-                  _GL_ARG_NONNULL ((1, 2)));
-_GL_CXXALIAS_RPL (setstate_r, int,
-                  (char *arg_state, struct random_data *rand_state));
-# else
-#  if !@HAVE_RANDOM_R@
-_GL_FUNCDECL_SYS (setstate_r, int,
-                  (char *arg_state, struct random_data *rand_state)
-                  _GL_ARG_NONNULL ((1, 2)));
-#  endif
-/* Need to cast, because on Haiku, the first parameter is
-                        void *arg_state.  */
-_GL_CXXALIAS_SYS_CAST (setstate_r, int,
-                       (char *arg_state, struct random_data *rand_state));
-# endif
-_GL_CXXALIASWARN (setstate_r);
-#elif defined GNULIB_POSIXCHECK
-# undef setstate_r
-# if HAVE_RAW_DECL_SETSTATE_R
-_GL_WARN_ON_USE (setstate_r, "setstate_r is unportable - "
-                 "use gnulib module random_r for portability");
-# endif
-#endif
-
 
 #if @GNULIB_REALLOC_POSIX@
 # if @REPLACE_REALLOC@
--- a/m4/stdlib_h.m4
+++ b/m4/stdlib_h.m4
@@ -19,9 +19,6 @@
 # include <sys/time.h>
 # include <sys/loadavg.h>
 #endif
-#if HAVE_RANDOM_H
-# include <random.h>
-#endif
     ]], [_Exit atoll canonicalize_file_name getloadavg getsubopt grantpt
     initstate initstate_r mbtowc mkdtemp mkostemp mkostemps mkstemp mkstemps
     posix_openpt ptsname ptsname_r qsort_r random random_r reallocarray
@@ -96,9 +93,6 @@
   HAVE_PTSNAME=1;            AC_SUBST([HAVE_PTSNAME])
   HAVE_PTSNAME_R=1;          AC_SUBST([HAVE_PTSNAME_R])
   HAVE_QSORT_R=1;            AC_SUBST([HAVE_QSORT_R])
-  HAVE_RANDOM=1;             AC_SUBST([HAVE_RANDOM])
-  HAVE_RANDOM_H=1;           AC_SUBST([HAVE_RANDOM_H])
-  HAVE_RANDOM_R=1;           AC_SUBST([HAVE_RANDOM_R])
   HAVE_REALLOCARRAY=1;       AC_SUBST([HAVE_REALLOCARRAY])
   HAVE_REALPATH=1;           AC_SUBST([HAVE_REALPATH])
   HAVE_RPMATCH=1;            AC_SUBST([HAVE_RPMATCH])
--- a/msdos/autogen/Makefile.in
+++ b/msdos/autogen/Makefile.in
@@ -602,8 +602,6 @@
 GNULIB_PUTS = @GNULIB_PUTS@
 GNULIB_PWRITE = @GNULIB_PWRITE@
 GNULIB_RAISE = @GNULIB_RAISE@
-GNULIB_RANDOM = @GNULIB_RANDOM@
-GNULIB_RANDOM_R = @GNULIB_RANDOM_R@
 GNULIB_RAWMEMCHR = @GNULIB_RAWMEMCHR@
 GNULIB_READ = @GNULIB_READ@
 GNULIB_READDIR = @GNULIB_READDIR@
@@ -802,9 +800,6 @@
 HAVE_PTSNAME_R = @HAVE_PTSNAME_R@
 HAVE_PWRITE = @HAVE_PWRITE@
 HAVE_RAISE = @HAVE_RAISE@
-HAVE_RANDOM = @HAVE_RANDOM@
-HAVE_RANDOM_H = @HAVE_RANDOM_H@
-HAVE_RANDOM_R = @HAVE_RANDOM_R@
 HAVE_RAWMEMCHR = @HAVE_RAWMEMCHR@
 HAVE_READDIR = @HAVE_READDIR@
 HAVE_READLINK = @HAVE_READLINK@
@@ -836,7 +831,6 @@
 HAVE_STRTOD = @HAVE_STRTOD@
 HAVE_STRTOLL = @HAVE_STRTOLL@
 HAVE_STRTOULL = @HAVE_STRTOULL@
-HAVE_STRUCT_RANDOM_DATA = @HAVE_STRUCT_RANDOM_DATA@
 HAVE_STRUCT_SIGACTION_SA_SIGACTION = @HAVE_STRUCT_SIGACTION_SA_SIGACTION@
 HAVE_STRUCT_TIMEVAL = @HAVE_STRUCT_TIMEVAL@
 HAVE_STRVERSCMP = @HAVE_STRVERSCMP@
@@ -1072,7 +1066,6 @@
 REPLACE_PUTENV = @REPLACE_PUTENV@
 REPLACE_PWRITE = @REPLACE_PWRITE@
 REPLACE_RAISE = @REPLACE_RAISE@
-REPLACE_RANDOM_R = @REPLACE_RANDOM_R@
 REPLACE_READ = @REPLACE_READ@
 REPLACE_READLINK = @REPLACE_READLINK@
 REPLACE_REALLOC = @REPLACE_REALLOC@
@@ -2393,9 +2386,6 @@
 @BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_POSIX_OPENPT''@|$(HAVE_POSIX_OPENPT)|g' \
 @BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_PTSNAME''@|$(HAVE_PTSNAME)|g' \
 @BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_PTSNAME_R''@|$(HAVE_PTSNAME_R)|g' \
-@BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_RANDOM''@|$(HAVE_RANDOM)|g' \
-@BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_RANDOM_H''@|$(HAVE_RANDOM_H)|g' \
-@BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_RANDOM_R''@|$(HAVE_RANDOM_R)|g' \
 @BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_REALPATH''@|$(HAVE_REALPATH)|g' \
 @BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_RPMATCH''@|$(HAVE_RPMATCH)|g' \
 @BUILDING_FOR_WINDOWSNT_FALSE@	      -e 's|@''HAVE_SECURE_GETENV''@|$(HAVE_SECURE_GETENV)|g' \
--- a/msdos/autogen/config.in
+++ b/msdos/autogen/config.in
@@ -726,9 +726,6 @@
 /* Define to 1 if the system has the type 'long long int'. */
 #undef HAVE_LONG_LONG_INT
 
-/* Define to 1 if you have the `lrand48' function. */
-#undef HAVE_LRAND48
-
 /* Define to 1 if you have the `lstat' function. */
 #undef HAVE_LSTAT
 
@@ -842,9 +839,6 @@
 /* Define to 1 if you have the <pwd.h> header file. */
 #undef HAVE_PWD_H
 
-/* Define to 1 if you have the `random' function. */
-#undef HAVE_RANDOM
-
 /* Define to 1 if you have the `readlink' function. */
 #undef HAVE_READLINK
 
--- a/msdos/sedlibmk.inp
+++ b/msdos/sedlibmk.inp
@@ -224,9 +224,7 @@
 /^HAVE_PCLOSE *=/s/@HAVE_PCLOSE@/1/
 /^HAVE_POPEN *=/s/@HAVE_POPEN@/1/
 /^HAVE_POSIX_SIGNALBLOCKING *=/s/@HAVE_POSIX_SIGNALBLOCKING@/1/
-/^HAVE_RANDOM_H *=/s/@HAVE_RANDOM_H@/1/
 /^HAVE_RAISE *=/s/@HAVE_RAISE@/1/
-/^HAVE_RANDOM *=/s/@HAVE_RANDOM@/1/
 /^HAVE_READDIR *=/s/@HAVE_READDIR@/1/
 /^HAVE_REWINDDIR *=/s/@HAVE_REWINDDIR@/1/
 /^HAVE_SETENV *=/s/@HAVE_SETENV@/1/
--- a/src/conf_post.h
+++ b/src/conf_post.h
@@ -117,15 +117,7 @@
 #endif
 #endif	/* HYBRID_MALLOC */
 
-/* We have to go this route, rather than the old hpux9 approach of
-   renaming the functions via macros.  The system's stdlib.h has fully
-   prototyped declarations, which yields a conflicting definition of
-   srand48; it tries to redeclare what was once srandom to be srand48.
-   So we go with HAVE_LRAND48 being defined.  */
 #ifdef HPUX
-#undef srandom
-#undef random
-#undef HAVE_RANDOM
 #undef HAVE_RINT
 #endif  /* HPUX */
 
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -2237,82 +2237,38 @@
 #endif
 }
 
-#ifndef HAVE_RANDOM
-#ifdef random
-#define HAVE_RANDOM
-#endif
-#endif
-
-/* Figure out how many bits the system's random number generator uses.
-   `random' and `lrand48' are assumed to return 31 usable bits.
-   BSD `rand' returns a 31 bit value but the low order bits are unusable;
-   so we'll shift it and treat it like the 15-bit USG `rand'.  */
-
-#ifndef RAND_BITS
-# ifdef HAVE_RANDOM
-#  define RAND_BITS 31
-# else /* !HAVE_RANDOM */
-#  ifdef HAVE_LRAND48
-#   define RAND_BITS 31
-#   define random lrand48
-#  else /* !HAVE_LRAND48 */
-#   define RAND_BITS 15
-#   if RAND_MAX == 32767
-#    define random rand
-#   else /* RAND_MAX != 32767 */
-#    if RAND_MAX == 2147483647
-#     define random() (rand () >> 16)
-#    else /* RAND_MAX != 2147483647 */
-#     ifdef USG
-#      define random rand
-#     else
-#      define random() (rand () >> 16)
-#     endif /* !USG */
-#    endif /* RAND_MAX != 2147483647 */
-#   endif /* RAND_MAX != 32767 */
-#  endif /* !HAVE_LRAND48 */
-# endif /* !HAVE_RANDOM */
-#endif /* !RAND_BITS */
-
-#ifdef HAVE_RANDOM
-typedef unsigned int random_seed;
-static void set_random_seed (random_seed arg) { srandom (arg); }
-#elif defined HAVE_LRAND48
-/* Although srand48 uses a long seed, this is unsigned long to avoid
-   undefined behavior on signed integer overflow in init_random.  */
-typedef unsigned long int random_seed;
-static void set_random_seed (random_seed arg) { srand48 (arg); }
-#else
-typedef unsigned int random_seed;
-static void set_random_seed (random_seed arg) { srand (arg); }
-#endif
+/* Permuted congruential generator with 32-output and 64-bit state. */
+static unsigned long long pcg32[2];
 
 void
 seed_random (void *seed, ptrdiff_t seed_size)
 {
-  random_seed arg = 0;
-  unsigned char *argp = (unsigned char *) &arg;
   unsigned char *seedp = seed;
+  pcg32[0] = 0xcbf29ce484222325ULL;
+  pcg32[1] = ~pcg32[0];
   for (ptrdiff_t i = 0; i < seed_size; i++)
-    argp[i % sizeof arg] ^= seedp[i];
-  set_random_seed (arg);
+    {
+      pcg32[0] ^= seedp[i];
+      pcg32[0] *= 0x00000100000001B3ULL;
+      pcg32[1] ^= seedp[i];
+      pcg32[1] *= 0x00000100000001B3ULL;
+    }
 }
 
 void
 init_random (void)
 {
-  random_seed v;
   bool success = false;
 
   /* First, try seeding the PRNG from the operating system's entropy
      source.  This approach is both fast and secure.  */
 #ifdef WINDOWSNT
-  success = w32_init_random (&v, sizeof v) == 0;
+  success = w32_init_random (&pcg32, sizeof pcg32) == 0;
 #else
   int fd = emacs_open ("/dev/urandom", O_RDONLY, 0);
   if (0 <= fd)
     {
-      success = emacs_read (fd, &v, sizeof v) == sizeof v;
+      success = emacs_read (fd, &pcg32, sizeof pcg32) == sizeof pcg32;
       close (fd);
     }
 #endif
@@ -2321,17 +2277,28 @@
      some systems, can be somewhat slow.  */
   if (!success)
     success = EQ (emacs_gnutls_global_init (), Qt)
-      && gnutls_rnd (GNUTLS_RND_NONCE, &v, sizeof v) == 0;
+      && gnutls_rnd (GNUTLS_RND_NONCE, &pcg32, sizeof pcg32) == 0;
 
   /* If _that_ didn't work, just use the current time value and PID.
      It's at least better than XKCD 221.  */
   if (!success)
     {
       struct timespec t = current_timespec ();
-      v = getpid () ^ t.tv_sec ^ t.tv_nsec;
+      seed_random (&t, sizeof(t));
     }
+}
 
-  set_random_seed (v);
+/*
+ * Return the next 32 bits from the PCG.
+ */
+unsigned long
+pcg32_gen (void)
+{
+  unsigned long long s = pcg32[0] & 0xffffffffffffffffULL;
+  pcg32[0] = pcg32[0] * 6364136223846793005ULL + (pcg32[1] | 1);
+  unsigned long x = (((s >> 18) ^ s) >> 27) & 0xffffffffUL;
+  unsigned rot = s >> 59;
+  return (x >> rot) | (x << ((-rot) & 31));
 }
 
 /*
@@ -2344,9 +2311,9 @@
 {
   EMACS_UINT val = 0;
   int i;
-  for (i = 0; i < (FIXNUM_BITS + RAND_BITS - 1) / RAND_BITS; i++)
-    val = (random () ^ (val << RAND_BITS)
-	   ^ (val >> (EMACS_INT_WIDTH - RAND_BITS)));
+  for (i = 0; i < (FIXNUM_BITS + 32 - 1) / 32; i++)
+    val = (pcg32_gen () ^ (val << 32)
+	   ^ (val >> (EMACS_INT_WIDTH - 32)));
   val ^= val >> (EMACS_INT_WIDTH - FIXNUM_BITS);
   return val & INTMASK;
 }