📄 cq.c
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struct defs { int cbits; /* No. of bits per char */ int ibits; /* int */ int sbits; /* short */ int lbits; /* long */ int ubits; /* unsigned */ int fbits; /* float */ int dbits; /* double */ float fprec; /* Smallest number that can be */ float dprec; /* significantly added to 1. */ int flgs; /* Print return codes, by section */ int flgm; /* Announce machine dependencies */ int flgd; /* give explicit diagnostics */ int flgl; /* Report local return codes. */ int rrc; /* recent return code */ int crc; /* Cumulative return code */ char rfs[8]; /* Return from section */ };main(n,args) /* C REFERENCE MANUAL */int n;char **args;{/* This program performs a series of tests on a C compiler,based on information in the C REFERENCE MANUALwhich appears as Appendix A to the book "The C ProgrammingLanguage" by Brian W. Kernighan and Dennis M. Ritchie(Prentice-Hall, 1978, $10.95). This Appendix is hereafterreferred to as "the Manual". The rules followed in writing this program are: 1. The entire program is written in legal C, according to the Manual. It should compile with no error messages, although some warning messages may be produced by some compilers. Failure to compile should be interpreted as a compiler error. 2. The program is clean, in that it does not make use of any features of the operating system on which it runs, with the sole exceptions of the printf() function, and an internal "options" routine, which is easily excised. 3. No global variables are used, except for the spec- ific purpose of testing the global variable facility. The program is divided into modules having names of theform snnn... These modules correspond to those sections of theManual, as identified by boldface type headings, in whichthere is something to test. For example, s241() correspondsto section 2.4.1 of the Manual (Integer constants) and teststhe facilities described therein. The module numberingscheme is ambiguous, especially when it names modulesreferring to more than one section; module s7813, for ex-ample, deals with sections 7.8 through 7.13. Nonetheless,it is surprisingly easy to find a section in the Manualcorresponding to a section of code, and vice versa. Note also that there seem to be "holes" in the program,at least from the point of view that there exist sections in theManual for which there is no corresponding code. Such holesarise from three causes: (a) there is nothing in that partic-ular section to test, (b) everything in that section is testedelsewhere, and (c) it was deemed advisable not to check cer-tain features like preprocessor or listing control features. Modules are called by a main program main(). The mod-ules that are called, and the sequence in which they are called, are determined by two lists in main(), in which themodule names appear. The first list (an extern statement)declares the module names to be external. The second (a stat-ic int statement) names the modules and defines the sequencein which they are called. There is no need for these liststo be in the same order, but it is probably a good idea to keepthem that way in the interest of clarity. Since there are nocross-linkages between modules, new modules may be added,or old ones deleted, simply by editing the lists, with oneexception: section s26, which pokes around at the hardwaretrying to figure out the characteristics of the machine thatit is running on, saves information that is subsequentlyused by sections s626, s72, and s757. If this program isto be broken up into smallish pieces, say for running ona microcomputer, take care to see that s26 is called beforecalling any of the latter three sections. The sizeof the lists, i.e., the number of modules to be called, isnot explicitly specified as a program parameter, but isdetermined dynamically using the sizeof operator. Communication between the main program and the modulestakes place in two ways. In all cases, a pointer to a structureis passed to the called module. The structure contains flagsthat will determine the type of information to be publishedby the module, and fields that may be written in by themodule. The former include "flgm" and "flgd", which, if setto a nonzero value, specify that machine dependencies are tobe announced or that error messages are to be printed, re-spectively. The called module's name, and the hardware char-acteristics probed in s26() comprise the latter. Also, in all cases, a return code is returned by the calledmodule. A return code of zero indicates that all has gone well;nonzero indicates otherwise. Since more than one type of errormay be detected by a module, the return code is a compositeof error indicators, which, individually, are given as numbersthat are powers of two. Thus, a return code of 10 indicatesthat two specific errors, 8 and 2, were detected. Whether ornot the codes returned by the modules are printed by the mainprogram is determined by setting "flgs" to 1 (resp. 0). The entire logic of the main program is contained in thehalf-dozen or so lines at the end. The somewhat cryptic statement: d0.rrc = (*sec[j])(pd0);in the for loop calls the modules. The rest of the code isreasonably straightforward. Finally, in each of the modules, there is the followingprologue: snnn(pd0) struct defs *pd0; { static char snnner[] = "snnn,er%d\n"; static char qsnnn[8] = "snnn "; char *ps, *pt; int rc; rc = 0; ps = qsnnn; pt = pd0->rfs; while(*pt++ = *ps++);used for housekeeping, handshaking and module initialization. */ extern s22(struct defs *), s241(struct defs *), s243(struct defs *), s244(struct defs *), s25(struct defs *), s26(struct defs *), s4(struct defs *), s61(struct defs *), s626(struct defs *), s71(struct defs *), s72(struct defs *), s757(struct defs *), s7813(struct defs *), s714(struct defs *), s715(struct defs *), s81(struct defs *), s84(struct defs *), s85(struct defs *), s86(struct defs *), s88(struct defs *), s9(struct defs *) ; int j; static int (*sec[])() = { s22, s241, s243, s244, s25, s26, s4, s61, s626, s71, s72, s757, s7813, s714, s715, s81, s84, s85, s86, s88, s9 }; static struct defs d0, *pd0; d0.flgs = 1; /* These flags dictate */ d0.flgm = 1; /* the verbosity of */ d0.flgd = 1; /* the program. */ d0.flgl = 1; pd0 = &d0; for (j=0; j<sizeof(sec) / sizeof(sec[0]); j++) { d0.rrc = (*sec[j])(pd0); d0.crc = d0.crc+d0.rrc; if(d0.flgs != 0) printf("Section %s returned %d.\n",d0.rfs,d0.rrc); } if(d0.crc == 0) printf("\nNo errors detected.\n"); else printf("\nFailed.\n"); return 0;}s22(pd0) /* 2.2 Identifiers (Names) */struct defs *pd0;{ int a234, a; int _, _234, A, rc; static char s22er[] = "s22,er%d\n"; static char qs22[8] = "s22 "; char *ps, *pt; /* Initialize */ rc = 0; ps = qs22; pt = pd0 -> rfs; while (*pt++ = *ps++); /* An identifier is a sequence of letters and digits; the first character must be a letter. The under- score _ counts as a letter. */ a=1; _=2; _234=3; a234=4; if(a+_+_234+a234 != 10) { rc = rc+1; if(pd0->flgd != 0) printf(s22er,1); } /* Upper and lower case letters are different. */ A = 2; if (A == a) { rc = rc+4; if (pd0->flgd != 0) printf(s22er,4); } return(rc);}s241(pd0) /* 2.4.1 Integer constants 2.4.2 Explicit long constants */struct defs *pd0;{ long pow2(); static char s241er[] = "s241,er%d\n"; static char qs241[8] = "s241 "; char *ps, *pt; int rc, j, lrc; static long g[39] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,6,0,8,0,12,0,16,0,18,0,20,0,24, 0,28,0,30,0,32,0,36}; long d[39], o[39], x[39]; rc = 0; lrc = 0; ps = qs241; pt = pd0 -> rfs; while (*pt++ = *ps++); /* An integer constant consisting of a sequence of digits is taken to be octal if it begins with 0 (digit zero), decimal otherwise. */ if ( 8 != 010 || 16 != 020 || 24 != 030 || 32 != 040 || 40 != 050 || 48 != 060 || 56 != 070 || 64 != 0100 || 72 != 0110 || 80 != 0120 || 9 != 0011 || 17 != 0021 || 25 != 0031 || 33 != 0041 || 41 != 0051 || 49 != 0061 || 57 != 0071 || 65 != 0101 || 73 != 0111 || 81 != 0121 ){ rc = rc+1; if( pd0->flgd != 0 ) printf(s241er,1); } /* A sequence of digits preceded by 0x or 0X (digit zero) is taken to be a hexadecimal integer. The hexadecimal digits include a or A through f or F with values 10 through 15. */ if ( 0x00abcdef != 0xabcdef || 0xabcdef != 0Xabcdef || 0Xabcdef != 0XAbcdef || 0XAbcdef != 0XABcdef || 0XABcdef != 0XABCdef || 0XABCdef != 0XABCDef || 0XABCDef != 0XABCDEf || 0XABCDEf != 0XABCDEF || 0xABCDEF != 11259375 ){ rc = rc+2; if( pd0->flgd != 0 ) printf(s241er,2); } /* A decimal constant whose value exceeds the largest signed machine integer is taken to be long; an octal or hex con- stant which exceeds the largest unsigned machine integer is likewise taken to be long. */ if ( sizeof 010000000000 != sizeof(long) /* 2**30 */ || sizeof 1073741824 != sizeof(long) /* ditto */ || sizeof 0x40000000 != sizeof(long) ){ /* " */ rc = rc+4; if( pd0->flgd != 0 ) printf(s241er,4); } /* A decimal, octal, or hexadecimal constant immediately followed by l (letter ell) or L is a long constant. */ if ( sizeof 67l != sizeof(long) || sizeof 67L != sizeof(long) || sizeof 067l != sizeof(long) || sizeof 067L != sizeof(long) || sizeof 0X67l != sizeof(long) || sizeof 0x67L != sizeof(long) ){ rc = rc+8; if( pd0 -> flgd != 0 ) printf(s241er,8); } /* Finally, we test to see that decimal (d), octal (o), and hexadecimal (x) constants representing the same values agree among themselves, and with computed values, at spec- ified points over an appropriate range. The points select- ed here are those with the greatest potential for caus- ing trouble, i.e., zero, 1-16, and values of 2**n and 2**n - 1 where n is some multiple of 4 or 6. Unfortunately, just what happens when a value is too big to fit in a long is undefined; however, it would be nice if what happened were at least consistent... */ for ( j=0; j<17; j++ ) g[j] = j; for ( j=18; j<39; ) { g[j] = pow2(g[j]); g[j-1] = g[j] - 1; j = j+2; } d[0] = 0; o[0] = 00; x[0] = 0x0; d[1] = 1; o[1] = 01; x[1] = 0x1; d[2] = 2; o[2] = 02; x[2] = 0x2; d[3] = 3; o[3] = 03; x[3] = 0x3; d[4] = 4; o[4] = 04; x[4] = 0x4; d[5] = 5; o[5] = 05; x[5] = 0x5; d[6] = 6; o[6] = 06; x[6] = 0x6; d[7] = 7; o[7] = 07; x[7] = 0x7; d[8] = 8; o[8] = 010; x[8] = 0x8; d[9] = 9; o[9] = 011; x[9] = 0x9; d[10] = 10; o[10] = 012; x[10] = 0xa; d[11] = 11; o[11] = 013; x[11] = 0xb; d[12] = 12; o[12] = 014; x[12] = 0xc; d[13] = 13; o[13] = 015; x[13] = 0xd; d[14] = 14; o[14] = 016; x[14] = 0xe; d[15] = 15; o[15] = 017; x[15] = 0xf; d[16] = 16; o[16] = 020; x[16] = 0x10; d[17] = 63; o[17] = 077; x[17] = 0x3f; d[18] = 64; o[18] = 0100; x[18] = 0x40; d[19] = 255; o[19] = 0377; x[19] = 0xff; d[20] = 256; o[20] = 0400; x[20] = 0x100; d[21] = 4095; o[21] = 07777; x[21] = 0xfff; d[22] = 4096; o[22] = 010000; x[22] = 0x1000; d[23] = 65535; o[23] = 0177777; x[23] = 0xffff; d[24] = 65536; o[24] = 0200000; x[24] = 0x10000; d[25] = 262143; o[25] = 0777777; x[25] = 0x3ffff; d[26] = 262144; o[26] = 01000000; x[26] = 0x40000; d[27] = 1048575; o[27] = 03777777; x[27] = 0xfffff; d[28] = 1048576; o[28] = 04000000; x[28] = 0x100000; d[29] = 16777215; o[29] = 077777777; x[29] = 0xffffff; d[30] = 16777216; o[30] = 0100000000; x[30] = 0x1000000; d[31] = 268435455; o[31] = 01777777777; x[31] = 0xfffffff; d[32] = 268435456; o[32] = 02000000000; x[32] = 0x10000000; d[33] = 1073741823; o[33] = 07777777777; x[33] = 0x3fffffff; d[34] = 1073741824; o[34] = 010000000000; x[34] = 0x40000000; d[35] = 4294967295; o[35] = 037777777777; x[35] = 0xffffffff; d[36] = 4294967296; o[36] = 040000000000; x[36] = 0x100000000; d[37] = 68719476735; o[37] = 0777777777777; x[37] = 0xfffffffff; d[38] = 68719476736; o[38] = 01000000000000; x[38] = 0x1000000000; /* WHEW! */ for (j=0; j<39; j++){ if ( g[j] != d[j] || d[j] != o[j] || o[j] != x[j]) { if( pd0 -> flgm != 0 ) {/* printf(s241er,16); save in case opinions change... */ printf("Decimal and octal/hex constants sometimes give\n"); printf(" different results when assigned to longs.\n"); }/* lrc = 1; save... */ } } if (lrc != 0) rc =16; return rc;}long pow2(n) /* Calculate 2**n by multiplying, not shifting */long n;{ long s; s = 1; while(n--) s = s*2; return s;}s243(pd0) /* 2.4.3 Character constants */struct defs *pd0;{ static char s243er[] = "s243,er%d\n"; static char qs243[8] = "s243 "; char *ps, *pt; int rc; char chars[256]; rc = 0; ps = qs243; pt = pd0->rfs; while(*pt++ = *ps++); /* One of the problems that arises when testing character constants is that of definition: What, exactly, is the character set? In order to guarantee a certain amount of machine independence, the character set we will use here is the set of characters writ- able as escape sequences in C, plus those characters used in writ- ing C programs, i.e., letters: ABCDEFGHIJKLMNOPQRSTUVWXYZ 26 abcdefghijklmnopqrstuvwxyz 26 numbers: 0123456789 10 special characters: ~!"#%&()_=-^|{}[]+;*:<>,.?/ 27 extra special characters: newline \n horizontal tab \t backspace \b carriage return \r form feed \f backslash \\ single quote \' 7 blank & NUL 2 --- 98 Any specific implementation of C may of course support additional characters. */ /* Since the value of a character constant is the numerical value of the character in the machine's character set, there should be a one-to-one correspondence between characters and values. */ zerofill(chars); chars['a'] = 1; chars['A'] = 1; chars['~'] = 1; chars['0'] = 1; chars['b'] = 1; chars['B'] = 1; chars['!'] = 1; chars['1'] = 1; chars['c'] = 1; chars['C'] = 1; chars['"'] = 1; chars['2'] = 1; chars['d'] = 1; chars['D'] = 1; chars['#'] = 1; chars['3'] = 1; chars['e'] = 1; chars['E'] = 1; chars['%'] = 1; chars['4'] = 1; chars['f'] = 1; chars['F'] = 1; chars['&'] = 1; chars['5'] = 1; chars['g'] = 1; chars['G'] = 1; chars['('] = 1; chars['6'] = 1; chars['h'] = 1; chars['H'] = 1; chars[')'] = 1; chars['7'] = 1; chars['i'] = 1; chars['I'] = 1; chars['_'] = 1; chars['8'] = 1; chars['j'] = 1; chars['J'] = 1; chars['='] = 1; chars['9'] = 1; chars['k'] = 1; chars['K'] = 1; chars['-'] = 1; chars['l'] = 1; chars['L'] = 1; chars['^'] = 1; chars['m'] = 1; chars['M'] = 1; chars['|'] = 1; chars['\n'] = 1; chars['n'] = 1; chars['N'] = 1; chars['\t'] = 1; chars['o'] = 1; chars['O'] = 1; chars['{'] = 1; chars['\b'] = 1; chars['p'] = 1; chars['P'] = 1; chars['}'] = 1; chars['\r'] = 1; chars['q'] = 1; chars['Q'] = 1; chars['['] = 1; chars['\f'] = 1; chars['r'] = 1; chars['R'] = 1; chars[']'] = 1; chars['s'] = 1; chars['S'] = 1; chars['+'] = 1; chars['\\'] = 1; chars['t'] = 1; chars['T'] = 1; chars[';'] = 1; chars['\''] = 1; chars['u'] = 1; chars['U'] = 1; chars['*'] = 1; chars['v'] = 1; chars['V'] = 1; chars[':'] = 1; chars['\0'] = 1; chars['w'] = 1; chars['W'] = 1; chars['<'] = 1; chars[' '] = 1; chars['x'] = 1; chars['X'] = 1; chars['>'] = 1; chars['y'] = 1; chars['Y'] = 1; chars[','] = 1; chars['z'] = 1; chars['Z'] = 1; chars['.'] = 1; chars['?'] = 1; chars['/'] = 1; if(sumof(chars) != 98){ rc = rc+1; if(pd0->flgd != 0) printf(s243er,1); } /* Finally, the escape \ddd consists of the backslash followed by 1, 2, or 3 octal digits which are taken to specify the desired character. */ if( '\0' != 0 || '\01' != 1 || '\02' != 2 || '\03' != 3 || '\04' != 4 || '\05' != 5 || '\06' != 6 || '\07' != 7 || '\10' != 8 || '\17' != 15 || '\20' != 16 || '\77' != 63 || '\100' != 64 || '\177' != 127 ){ rc = rc+8; if(pd0->flgd != 0) printf(s243er,8); } return rc;}zerofill(x)char *x;{ int j; for (j=0; j<256; j++) *x++ = 0;}sumof(x)char *x;{ char *p; int total, j; p = x; total = 0; for(j=0; j<256; j++) total = total+ *p++; return total;}s244(pd0)struct defs *pd0;{ double a[8]; int rc, lrc, j; static char s244er[] = "s244,er%d\n"; static char qs244[8] = "s244 "; char *ps, *pt; ps = qs244; pt = pd0->rfs; while(*pt++ = *ps++); rc = 0; lrc = 0; /* Unfortunately, there's not a lot we can do with floating constants. We can check to see that the various representations can be com- piled, that the conversion is such that they yield the same hard- ware representations in all cases, and that all representations thus checked are double precision. */ a[0] = .1250E+04; a[1] = 1.250E3; a[2] = 12.50E02; a[3] = 125.0e+1; a[4] = 1250e00; a[5] = 12500.e-01; a[6] = 125000e-2;
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