diff --git a/.github/workflows/windows-msvc.yml b/.github/workflows/windows-msvc.yml
index 03211301c..0a2e7d800 100644
--- a/.github/workflows/windows-msvc.yml
+++ b/.github/workflows/windows-msvc.yml
@@ -178,18 +178,14 @@ jobs:
           # sed -i '/AT_SETUP(\[runtime check: write to internal storage (1)\])/a AT_SKIP_IF(\[true\])' tests/testsuite.src/run_misc.at
           sed -i '/run_misc/{N;/write to internal storage (1)/{N;N;N;N;s/traceon/traceon; echo "workflow:1">"$at_check_line_file"; at_fn_check_skip 77/;}}' tests/testsuite
 
-        # Fail two tests that behave differently under MSVC Debug
+        # Fail tests that behave differently under MSVC Debug
         # - System routine CBL_GC_HOSTED: fails because libcob is linked with the debug version
         #   of the C runtime while the generated module is linked with the release version
-        # - PROGRAM COLLATING SEQUENCE: fails because of a data loss in a cast, due
-        #   to lack of specific handling of LOW/HIGH-VALUE for NATIONAL alphabets
-        #   (see typeck.c:cb_validate_collating)
       - name: Adjust testsuite for Debug target
         if: ${{ matrix.target == 'Debug' }}
         shell: C:\shells\msys2bash.cmd {0}
         run: |
           sed -i '/run_extensions/{N;/System routine CBL_GC_HOSTED/{N;s/at_xfail=no/at_xfail=yes/;}}' tests/testsuite
-          sed -i '/syn_definition/{N;/PROGRAM COLLATING SEQUENCE/{N;s/at_xfail=no/at_xfail=yes/;}}' tests/testsuite
 
       - name: Run testsuite
         run: |
diff --git a/cobc/ChangeLog b/cobc/ChangeLog
index 8c5853b8e..fc35cad4e 100644
--- a/cobc/ChangeLog
+++ b/cobc/ChangeLog
@@ -177,6 +177,25 @@
 	  also forces -E, -foneline-deps, -MT=copybooks, disables errors on
 	  missing copybooks and removes output on stdout
 
+2024-02-26  David Declerck <david.declerck@ocamlpro.com>
+
+	BUG #948: comparison with HIGH-VALUE in presence of collating sequences
+	* tree.h: add low_value and high_value fields to hold the low
+	  and high values used by the program collating sequence
+	* tree.c: initialize the low_value and high_value fields
+	  to reasonable default values
+	* typeck.c: replace cob_refer_ascii and cob_refer_ebcdic by
+	  ebcdic_to_ascii and ascii_to_ebcdic; add load_collating_table
+	  to load the tables; modify cb_validate_collating to call
+	  load_collating_table and set low_value and high_value
+	  fields modify validate_alphabet to use the new tables
+	* cobc.h: export the new symbols defined in typeck.c
+	* codegen.c: replace hard-coded 0 and 255 / 0xff contants with
+	  the low_value and high_value fields where appropriate; move
+	  the cob_all_low and cob_all_high fields from global to local;
+	  adjust the output_collating_tables function to use the tables and
+	  functions defined in typeck.c; set the new module field low_value
+
 2024-02-19  Boris Eng <boris.eng@ocamlpro.com>
 
 	* parser.y (screen_value_clause): replaced basic literals by literals
diff --git a/cobc/cobc.c b/cobc/cobc.c
index de9c1d6f1..975b7e201 100644
--- a/cobc/cobc.c
+++ b/cobc/cobc.c
@@ -4230,6 +4230,10 @@ process_command_line (const int argc, char **argv)
 			cb_flag_alt_ebcdic ? "alternate" : "default");
 	}
 
+	if (cob_load_collation (cb_ebcdic_table, ebcdic_to_ascii, ascii_to_ebcdic) < 0) {
+		cobc_err_exit (_("invalid parameter: %s"), "-febcdic-table");
+	}
+
 	/* Exit on missing options */
 #ifdef COB_INTERNAL_XREF
 	if (cb_listing_xref && !cb_listing_outputfile) {
diff --git a/cobc/cobc.h b/cobc/cobc.h
index 2c1bcf2ca..c276e08d8 100644
--- a/cobc/cobc.h
+++ b/cobc/cobc.h
@@ -624,6 +624,11 @@ extern int		yyparse (void);
 /* typeck.c */
 extern size_t		suppress_warn;	/* no warnings for internal generated stuff */
 
+extern cob_u8_t ebcdic_to_ascii[256];
+extern cob_u8_t ascii_to_ebcdic[256];
+
+void load_collating_tables (void);
+
 /* error.c */
 #define CB_MSG_STYLE_GCC	0
 #define CB_MSG_STYLE_MSC	1U
diff --git a/cobc/codegen.c b/cobc/codegen.c
index c46d67f24..8a5e124c6 100644
--- a/cobc/codegen.c
+++ b/cobc/codegen.c
@@ -2515,11 +2515,11 @@ static void
 output_low_value (void)
 {
 	if (gen_figurative & CB_NEED_LOW) {
-		output ("static cob_field cob_all_low\t= ");
-		output ("{1, ");
-		output ("(cob_u8_ptr)\"\\0\", ");
-		output ("&cob_all_attr};");
-		output_newline ();
+		output_local ("static cob_field cob_all_low\t= ");
+		output_local ("{1, ");
+		output_local ("(cob_u8_ptr)\"\\x%02x\", ", current_prog->low_value);
+		output_local ("&cob_all_attr};");
+		output_local ("\n");
 	}
 }
 
@@ -2527,11 +2527,11 @@ static void
 output_high_value (void)
 {
 	if (gen_figurative & CB_NEED_HIGH) {
-		output ("static cob_field cob_all_high\t= ");
-		output ("{1, ");
-		output ("(cob_u8_ptr)\"\\xff\", ");
-		output ("&cob_all_attr};");
-		output_newline ();
+		output_local ("static cob_field cob_all_high\t= ");
+		output_local ("{1, ");
+		output_local ("(cob_u8_ptr)\"\\x%02x\", ", current_prog->high_value);
+		output_local ("&cob_all_attr};");
+		output_local ("\n");
 	}
 }
 
@@ -2615,8 +2615,6 @@ output_literals_figuratives_and_constants (void)
 
 	if (gen_figurative) {
 		output_newline ();
-		output_low_value ();
-		output_high_value ();
 		output_quote ();
 		output_space ();
 		output_zero ();
@@ -2654,18 +2652,6 @@ output_colseq_table_field (const char * field_name, const char * table_name)
 static void
 output_collating_tables (void)
 {
-	cob_u8_t ebcdic_to_ascii[256];
-	cob_u8_t ascii_to_ebcdic[256];
-
-	/* Load the collating tables if needed */
-	if (gen_ascii_ebcdic || gen_ebcdic_ascii) {
-		if (cob_load_collation (cb_ebcdic_table,
-					gen_ebcdic_ascii ? ebcdic_to_ascii : NULL,
-					gen_ascii_ebcdic ? ascii_to_ebcdic : NULL) < 0) {
-			cobc_err_exit (_("invalid parameter: %s"), "-febcdic-table");
-		}
-	}
-
 	if (gen_native) {
 		output_storage ("\n/* NATIVE table */\n");
 		output_colseq_table ("cob_native", NULL);
@@ -4277,9 +4263,9 @@ output_funcall_typed (struct cb_funcall *p, const char type)
 		} else if (p->argv[1] == cb_zero) {
 			output (") - '0')");
 		} else if (p->argv[1] == cb_low) {
-			output ("))");
+			output (") - %d)", current_prog->low_value);
 		} else if (p->argv[1] == cb_high) {
-			output (") - 255)");
+			output (") - %d)", current_prog->high_value);
 		} else if (CB_LITERAL_P (p->argv[1])) {
 			output_char (") - ", CB_LITERAL (p->argv[1])->data[0], ")");
 		} else {
@@ -5064,10 +5050,10 @@ output_initialize_to_value (struct cb_field *f, cb_tree x,
 			output_figurative (x, f, ' ', init_occurs);
 			return;
 		} else if (value == cb_low) {
-			output_figurative (x, f, 0, init_occurs);
+			output_figurative (x, f, current_prog->low_value, init_occurs);
 			return;
 		} else if (value == cb_high) {
-			output_figurative (x, f, 255, init_occurs);
+			output_figurative (x, f, current_prog->high_value, init_occurs);
 			return;
 		} else if (value == cb_quote) {
 			if (cb_flag_apostrophe) {
@@ -10810,9 +10796,9 @@ output_class_name_definition (struct cb_class_name *p)
 			} else if (x == cb_null) {
 				vals[0] = 1;
 			} else if (x == cb_low) {
-				vals[0] = 1;
+				vals[current_prog->low_value] = 1;
 			} else if (x == cb_high) {
-				vals[255] = 1;
+				vals[current_prog->high_value] = 1;
 			} else {
 				size = CB_LITERAL (x)->size;
 				data = CB_LITERAL (x)->data;
@@ -14157,6 +14143,12 @@ codegen_internal (struct cb_program *prog, const int subsequent_call)
 			output_local ("\n");
 		}
 	}
+
+	/* Low and high values */
+	if (gen_figurative) {
+		output_low_value ();
+		output_high_value ();
+	}
 }
 
 void
diff --git a/cobc/scanner.l b/cobc/scanner.l
index 878e660e9..dd7e21c52 100644
--- a/cobc/scanner.l
+++ b/cobc/scanner.l
@@ -1347,10 +1347,6 @@ static cob_u8_t
 scan_ebcdic_char (int c)
 {
 	char buff[10];	       /* Arbitrary limit, mostly for error-reporting */
-#ifndef COB_EBCDIC_MACHINE
-	static  cob_u8_t ebcdic_to_ascii[256] ;
-	static  int ebcdic_to_ascii_initialized = 0 ;
-#endif
 	unsigned int j = 0;
 	do {
 		buff[j++] = (char)c;
@@ -1367,20 +1363,7 @@ scan_ebcdic_char (int c)
 #ifdef COB_EBCDIC_MACHINE
 	return (cob_u8_t) c;
 #else
-	if (!ebcdic_to_ascii_initialized ) {
-		if (cob_load_collation (cb_ebcdic_table, ebcdic_to_ascii, NULL) < 0) {
-			cb_error (_("invalid parameter: %s"), "-febcdic-table");
-			ebcdic_to_ascii_initialized = -1;
-		} else {
-			ebcdic_to_ascii_initialized = 1;
-		}
-	}
-
-	if (ebcdic_to_ascii_initialized > 0) {
-		return ebcdic_to_ascii[c];
-	} else {
-		return '?';
-	}
+	return ebcdic_to_ascii[c];
 #endif
 }
 
diff --git a/cobc/tree.c b/cobc/tree.c
index 0e2f9bb18..6e781ed9c 100644
--- a/cobc/tree.c
+++ b/cobc/tree.c
@@ -2193,6 +2193,10 @@ cb_build_program (struct cb_program *last_program, const int nest_level)
 	p->decimal_point = '.';
 	p->currency_symbol = '$';
 	p->numeric_separator = ',';
+	p->low_value = 0;
+	p->high_value = 255;
+	p->low_value_n = 0;
+	p->high_value_n = 65535;
 	if (cb_call_extfh) {
 		p->extfh = cobc_parse_strdup (cb_call_extfh);
 	}
diff --git a/cobc/tree.h b/cobc/tree.h
index 19878838f..0c3d0679c 100644
--- a/cobc/tree.h
+++ b/cobc/tree.h
@@ -1916,6 +1916,10 @@ struct cb_program {
 	unsigned char	decimal_point;			/* '.' or ',' */
 	unsigned char	currency_symbol;		/* '$' or user-specified */
 	unsigned char	numeric_separator;		/* ',' or '.' */
+	cob_u8_t	low_value;			/* Low-value for this program */
+	cob_u8_t	high_value;			/* High-value for this program */
+	cob_u16_t	low_value_n;			/* National Low-value */
+	cob_u16_t	high_value_n;			/* National High-value  */
 	enum cob_module_type	prog_type;			/* Program type (program = 0, function = 1) */
 	cb_tree			entry_convention;	/* ENTRY convention / PROCEDURE convention */
 	struct literal_list	*decimal_constants;
diff --git a/cobc/typeck.c b/cobc/typeck.c
index 3f87068dd..26825d397 100644
--- a/cobc/typeck.c
+++ b/cobc/typeck.c
@@ -196,79 +196,10 @@ static const unsigned char	expr_prio[256] = {
 static unsigned char		expr_prio[256];
 #endif
 
-#ifdef	COB_EBCDIC_MACHINE
-/* EBCDIC referring to ASCII */
-static const unsigned char	cob_refer_ascii[256] = {
-	0x00, 0x01, 0x02, 0x03, 0x37, 0x2D, 0x2E, 0x2F,
-	0x16, 0x05, 0x25, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
-	0x10, 0x11, 0x12, 0x13, 0x3C, 0x3D, 0x32, 0x26,
-	0x18, 0x19, 0x3F, 0x27, 0x1C, 0x1D, 0x1E, 0x1F,
-	0x40, 0x5A, 0x7F, 0x7B, 0x5B, 0x6C, 0x50, 0x7D,
-	0x4D, 0x5D, 0x5C, 0x4E, 0x6B, 0x60, 0x4B, 0x61,
-	0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,
-	0xF8, 0xF9, 0x7A, 0x5E, 0x4C, 0x7E, 0x6E, 0x6F,
-	0x7C, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7,
-	0xC8, 0xC9, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6,
-	0xD7, 0xD8, 0xD9, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6,
-	0xE7, 0xE8, 0xE9, 0xAD, 0xE0, 0xBD, 0x5F, 0x6D,
-	0x79, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
-	0x88, 0x89, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96,
-	0x97, 0x98, 0x99, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6,
-	0xA7, 0xA8, 0xA9, 0xC0, 0x6A, 0xD0, 0xA1, 0x07,
-	0x68, 0xDC, 0x51, 0x42, 0x43, 0x44, 0x47, 0x48,
-	0x52, 0x53, 0x54, 0x57, 0x56, 0x58, 0x63, 0x67,
-	0x71, 0x9C, 0x9E, 0xCB, 0xCC, 0xCD, 0xDB, 0xDD,
-	0xDF, 0xEC, 0xFC, 0xB0, 0xB1, 0xB2, 0x3E, 0xB4,
-	0x45, 0x55, 0xCE, 0xDE, 0x49, 0x69, 0x9A, 0x9B,
-	0xAB, 0x9F, 0xBA, 0xB8, 0xB7, 0xAA, 0x8A, 0x8B,
-	0xB6, 0xB5, 0x62, 0x4F, 0x64, 0x65, 0x66, 0x20,
-	0x21, 0x22, 0x70, 0x23, 0x72, 0x73, 0x74, 0xBE,
-	0x76, 0x77, 0x78, 0x80, 0x24, 0x15, 0x8C, 0x8D,
-	0x8E, 0x41, 0x06, 0x17, 0x28, 0x29, 0x9D, 0x2A,
-	0x2B, 0x2C, 0x09, 0x0A, 0xAC, 0x4A, 0xAE, 0xAF,
-	0x1B, 0x30, 0x31, 0xFA, 0x1A, 0x33, 0x34, 0x35,
-	0x36, 0x59, 0x08, 0x38, 0xBC, 0x39, 0xA0, 0xBF,
-	0xCA, 0x3A, 0xFE, 0x3B, 0x04, 0xCF, 0xDA, 0x14,
-	0xE1, 0x8F, 0x46, 0x75, 0xFD, 0xEB, 0xEE, 0xED,
-	0x90, 0xEF, 0xB3, 0xFB, 0xB9, 0xEA, 0xBB, 0xFF
-};
-#else
-/* ASCII referring to EBCDIC */
-static const unsigned char	cob_refer_ebcdic[256] = {
-	0x00, 0x01, 0x02, 0x03, 0xEC, 0x09, 0xCA, 0x7F,
-	0xE2, 0xD2, 0xD3, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
-	0x10, 0x11, 0x12, 0x13, 0xEF, 0xC5, 0x08, 0xCB,
-	0x18, 0x19, 0xDC, 0xD8, 0x1C, 0x1D, 0x1E, 0x1F,
-	0xB7, 0xB8, 0xB9, 0xBB, 0xC4, 0x0A, 0x17, 0x1B,
-	0xCC, 0xCD, 0xCF, 0xD0, 0xD1, 0x05, 0x06, 0x07,
-	0xD9, 0xDA, 0x16, 0xDD, 0xDE, 0xDF, 0xE0, 0x04,
-	0xE3, 0xE5, 0xE9, 0xEB, 0x14, 0x15, 0x9E, 0x1A,
-	0x20, 0xC9, 0x83, 0x84, 0x85, 0xA0, 0xF2, 0x86,
-	0x87, 0xA4, 0xD5, 0x2E, 0x3C, 0x28, 0x2B, 0xB3,
-	0x26, 0x82, 0x88, 0x89, 0x8A, 0xA1, 0x8C, 0x8B,
-	0x8D, 0xE1, 0x21, 0x24, 0x2A, 0x29, 0x3B, 0x5E,
-	0x2D, 0x2F, 0xB2, 0x8E, 0xB4, 0xB5, 0xB6, 0x8F,
-	0x80, 0xA5, 0x7C, 0x2C, 0x25, 0x5F, 0x3E, 0x3F,
-	0xBA, 0x90, 0xBC, 0xBD, 0xBE, 0xF3, 0xC0, 0xC1,
-	0xC2, 0x60, 0x3A, 0x23, 0x40, 0x27, 0x3D, 0x22,
-	0xC3, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
-	0x68, 0x69, 0xAE, 0xAF, 0xC6, 0xC7, 0xC8, 0xF1,
-	0xF8, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70,
-	0x71, 0x72, 0xA6, 0xA7, 0x91, 0xCE, 0x92, 0xA9,
-	0xE6, 0x7E, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
-	0x79, 0x7A, 0xAD, 0xA8, 0xD4, 0x5B, 0xD6, 0xD7,
-	0x9B, 0x9C, 0x9D, 0xFA, 0x9F, 0xB1, 0xB0, 0xAC,
-	0xAB, 0xFC, 0xAA, 0xFE, 0xE4, 0x5D, 0xBF, 0xE7,
-	0x7B, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
-	0x48, 0x49, 0xE8, 0x93, 0x94, 0x95, 0xA2, 0xED,
-	0x7D, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50,
-	0x51, 0x52, 0xEE, 0x96, 0x81, 0x97, 0xA3, 0x98,
-	0x5C, 0xF0, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
-	0x59, 0x5A, 0xFD, 0xF5, 0x99, 0xF7, 0xF6, 0xF9,
-	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
-	0x38, 0x39, 0xDB, 0xFB, 0x9A, 0xF4, 0xEA, 0xFF
-};
-#endif
+/* ASCII/EBCDIC translation tables  */
+
+cob_u8_t ebcdic_to_ascii[256];
+cob_u8_t ascii_to_ebcdic[256];
 
 /* System routines */
 
@@ -3815,7 +3746,7 @@ get_value (cb_tree x)
 }
 
 static int
-cb_validate_collating (cb_tree collating_sequence)
+cb_validate_collating (struct cb_program *prog, cb_tree collating_sequence)
 {
 	cb_tree		x;
 
@@ -3829,19 +3760,43 @@ cb_validate_collating (cb_tree collating_sequence)
 			    cb_name (collating_sequence));
 		return 1;
 	}
-	if (CB_ALPHABET_NAME (x)->alphabet_type != CB_ALPHABET_CUSTOM) {
+
+#ifdef COB_EBCDIC_MACHINE
+	if (CB_ALPHABET_NAME (x)->alphabet_type == CB_ALPHABET_ASCII) {
+                prog->low_value = ascii_to_ebcdic[0x00];
+                prog->high_value = ascii_to_ebcdic[0xff];
+#else
+	if (CB_ALPHABET_NAME (x)->alphabet_type == CB_ALPHABET_EBCDIC) {
+                prog->low_value = ebcdic_to_ascii[0x00];
+                prog->high_value = ebcdic_to_ascii[0xff];
+#endif
+	} else if (CB_ALPHABET_NAME (x)->alphabet_type == CB_ALPHABET_CUSTOM) {
+		if (CB_ALPHABET_NAME (x)->alphabet_target == CB_ALPHABET_ALPHANUMERIC) {
+			prog->low_value = (cob_u8_t)CB_ALPHABET_NAME (x)->low_val_char;
+			prog->high_value = (cob_u8_t)CB_ALPHABET_NAME (x)->high_val_char;
+		} else /* CB_ALPHABET_NATIONAL */ {
+			prog->low_value_n = (cob_u16_t)CB_ALPHABET_NAME (x)->low_val_char;
+			prog->high_value_n = (cob_u16_t)CB_ALPHABET_NAME (x)->high_val_char;
+		}
+	} else {
 		return 0;
 	}
-	if (CB_ALPHABET_NAME (x)->low_val_char) {
-		cb_low = cb_build_alphanumeric_literal ("\0", (size_t)1);
-		CB_LITERAL(cb_low)->data[0] = (unsigned char)CB_ALPHABET_NAME (x)->low_val_char;
-		CB_LITERAL(cb_low)->all = 1;
-	}
-	if (CB_ALPHABET_NAME (x)->high_val_char != 255){
-		cb_high = cb_build_alphanumeric_literal ("\0", (size_t)1);
-		CB_LITERAL(cb_high)->data[0] = (unsigned char)CB_ALPHABET_NAME (x)->high_val_char;
-		CB_LITERAL(cb_high)->all = 1;
+
+	if (CB_ALPHABET_NAME (x)->alphabet_target == CB_ALPHABET_ALPHANUMERIC) {
+		if (prog->low_value) {
+			cb_low = cb_build_alphanumeric_literal ("\0", (size_t)1);
+			CB_LITERAL(cb_low)->data[0] = prog->low_value;
+			CB_LITERAL(cb_low)->all = 1;
+		}
+		if (prog->high_value != 255){
+			cb_high = cb_build_alphanumeric_literal ("\0", (size_t)1);
+			CB_LITERAL(cb_high)->data[0] = prog->high_value;
+			CB_LITERAL(cb_high)->all = 1;
+		}
+	} else /* CB_ALPHABET_NATIONAL */ {
+		/* TODO: LOW/HIGH-VALUE for national */
 	}
+
 	return 0;
 }
 
@@ -3884,6 +3839,8 @@ validate_alphabet (cb_tree alphabet)
 			*entry = n;
 			entry++;
 		}
+		ap->low_val_char = 0;
+		ap->high_val_char = 255;
 		return;
 	}
 
@@ -3892,12 +3849,19 @@ validate_alphabet (cb_tree alphabet)
 		register int	*entry = ap->values;
 		for (n = 0; n < COB_MAX_CHAR_ALPHANUMERIC + 1; n++) {
 #ifdef	COB_EBCDIC_MACHINE
-			*entry = (int)cob_refer_ascii[n];
+			*entry = (int)ascii_to_ebcdic[n];
 #else
 			*entry = n;
 #endif
 			entry++;
 		}
+#ifdef	COB_EBCDIC_MACHINE
+		ap->low_val_char = ascii_to_ebcdic[0x00];
+		ap->high_val_char = ascii_to_ebcdic[0xff];
+#else
+		ap->low_val_char = 0;
+		ap->high_val_char = 255;
+#endif
 		memcpy (ap->alphachr, ap->values, memsize);
 		return;
 	}
@@ -3909,11 +3873,17 @@ validate_alphabet (cb_tree alphabet)
 #ifdef	COB_EBCDIC_MACHINE
 			*entry = n;
 #else
-			*entry = (int)cob_refer_ebcdic[n];
+			*entry = (int)ebcdic_to_ascii[n];
 #endif
 			entry++;
 		}
-		
+#ifdef	COB_EBCDIC_MACHINE
+		ap->low_val_char = 0;
+		ap->high_val_char = 255;
+#else
+		ap->low_val_char = ebcdic_to_ascii[0x00];
+		ap->high_val_char = ebcdic_to_ascii[0xff];
+#endif
 		memcpy (ap->alphachr, ap->values, memsize);
 		return;
 	}
@@ -4316,10 +4286,10 @@ cb_validate_program_environment (struct cb_program *prog)
 	}
 
 	/* Resolve the program collating sequences */
-	if (cb_validate_collating (prog->collating_sequence)) {
+	if (cb_validate_collating (prog, prog->collating_sequence)) {
 		prog->collating_sequence = NULL;
 	};
-	if (cb_validate_collating (prog->collating_sequence_n)) {
+	if (cb_validate_collating (prog, prog->collating_sequence_n)) {
 		prog->collating_sequence_n = NULL;
 	};
 
diff --git a/libcob/ChangeLog b/libcob/ChangeLog
index 8b440116e..ed3304c16 100644
--- a/libcob/ChangeLog
+++ b/libcob/ChangeLog
@@ -238,6 +238,12 @@
 	FR #488: using state structures instead of state vars for strings
 	* strings.c: moved static variables to structures
 
+2024-02-26  David Declerck <david.declerck@ocamlpro.com>
+
+	BUG #948: comparison with HIGH-VALUE in presence of collating sequences
+	* strings.c: use the collating_sequence field of cob_module to
+	  determine the low value instead of the hard-coded constant "\0"
+
 2024-01-25  David Declerck <david.declerck@ocamlpro.com>
 
 	FR #459: support COLLATING SEQUENCE clause on SELECT / INDEXED files
diff --git a/libcob/strings.c b/libcob/strings.c
index f107cfdb0..51c3bf46c 100644
--- a/libcob/strings.c
+++ b/libcob/strings.c
@@ -108,6 +108,16 @@ static cob_field		str_cob_low;
 
 /* Local functions */
 
+static COB_INLINE COB_A_INLINE void
+cob_update_low_value (void)
+{
+	if (COB_MODULE_PTR->collating_sequence != NULL) {
+		str_cob_low.data = (cob_u8_ptr)&COB_MODULE_PTR->collating_sequence[0];
+	} else {
+		str_cob_low.data = (cob_u8_ptr)"\0";
+	}
+}
+
 static void
 cob_str_memcpy (cob_field *dst, unsigned char *src, const int size)
 {
@@ -454,9 +464,11 @@ inspect_common (
 	}
 
 	if (unlikely (!f1)) {
+		cob_update_low_value ();
 		f1 = &str_cob_low;
 	}
 	if (unlikely (!f2)) {
+		cob_update_low_value ();
 		f2 = &str_cob_low;
 	}
 
@@ -737,9 +749,11 @@ cob_inspect_converting_intern (
 	}
 
 	if (unlikely (!f1)) {
+		cob_update_low_value ();
 		f1 = &str_cob_low;
 	}
 	if (unlikely (!f2)) {
+		cob_update_low_value ();
 		f2 = &str_cob_low;
 	}
 	if (f1->size != f2->size) {
diff --git a/tests/testsuite.src/run_misc.at b/tests/testsuite.src/run_misc.at
index cd7cf27e6..a7a230b0e 100644
--- a/tests/testsuite.src/run_misc.at
+++ b/tests/testsuite.src/run_misc.at
@@ -4003,6 +4003,44 @@ AT_CHECK([$COBCRUN_DIRECT ./ebcdic], [0], [], [])
 AT_CLEANUP
 
 
+AT_SETUP([SEARCH ALL with non-0xff HIGH-VALUE])
+AT_KEYWORDS([runmisc default-colseq])
+
+AT_DATA([prog.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog.
+       ENVIRONMENT DIVISION.
+       CONFIGURATION SECTION.
+       OBJECT-COMPUTER. x86,
+           PROGRAM COLLATING SEQUENCE IS alpha-ebcdic.
+       SPECIAL-NAMES.
+           ALPHABET alpha-ebcdic IS EBCDIC.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01  TAB.
+         02 TAB-ELT   OCCURS 3
+                      ASCENDING KEY TAB-KEY
+                      INDEXED BY TI.
+           05 TAB-KEY PIC X.
+       PROCEDURE DIVISION.
+           MOVE HIGH-VALUE TO TAB
+           MOVE "1" TO TAB-ELT (1)
+      *    DISPLAY "|" TAB "|"
+           SEARCH ALL TAB-ELT
+              AT END
+                 DISPLAY '"1" NOT FOUND'
+              WHEN TAB-KEY (TI) = "1"
+                 CONTINUE
+           END-SEARCH
+           STOP RUN.
+])
+
+AT_CHECK([$COMPILE -febcdic-table=ebcdic500_latin1 prog.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog], [0], [], [])
+
+AT_CLEANUP
+
+
 AT_SETUP([PIC ZZZ-, ZZZ+])
 AT_KEYWORDS([runmisc editing])
 
@@ -15131,3 +15169,370 @@ AT_CHECK([COB_PROF_ENABLE=1 COB_PROF_FILE=prof.csv $COBCRUN_DIRECT ./caller], [0
 ])
 
 AT_CLEANUP
+
+
+# See bug #948 - Comparison with HIGH-VALUE in presence of collating sequences
+AT_SETUP([LOW/HIGH-VALUE when using non-native program collating sequence])
+AT_KEYWORDS([LOW-VALUE HIGH-VALUE ALPHABET EBCDIC ASCII])
+
+AT_DATA([prog1.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog.
+       ENVIRONMENT DIVISION.
+       CONFIGURATION SECTION.
+       OBJECT-COMPUTER. x86,
+           PROGRAM COLLATING SEQUENCE IS alpha-custom.
+       SPECIAL-NAMES.
+           ALPHABET alpha-custom IS
+               64 THRU 1
+               65 THRU 192
+               256 THRU 193.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 LV-ORD PIC 999.
+       01 LV     PIC X.
+       88 IS-LV VALUE LOW-VALUE.
+       01 HV-ORD PIC 999.
+       01 HV     PIC X.
+       88 IS-HV VALUE HIGH-VALUE.
+       PROCEDURE DIVISION.
+           MOVE LOW-VALUE TO LV.
+           MOVE HIGH-VALUE TO HV.
+           MOVE FUNCTION ORD (LOW-VALUE) TO LV-ORD.
+           MOVE FUNCTION ORD (HIGH-VALUE) TO HV-ORD.
+           DISPLAY "LOW-VALUE: " LV-ORD
+                 " HIGH-VALUE: " HV-ORD.
+           IF LV = LOW-VALUE AND IS-LV
+             DISPLAY "LOW-VALUE OK"
+           ELSE
+             DISPLAY "LOW-VALUE KO"
+           END-IF.
+           IF HV = HIGH-VALUE AND IS-HV
+             DISPLAY "HIGH-VALUE OK"
+           ELSE
+             DISPLAY "HIGH-VALUE KO"
+           END-IF.
+           IF "X" > LOW-VALUE AND "X" > LV
+              DISPLAY "X > LOW-VALUE"
+           ELSE
+              DISPLAY "X < LOW-VALUE"
+           END-IF.
+           IF "X" < HIGH-VALUE AND "X" < HV
+              DISPLAY "X < HIGH-VALUE"
+           ELSE
+              DISPLAY "X > HIGH-VALUE"
+           END-IF.
+           STOP RUN.
+])
+
+AT_CHECK([$COMPILE prog1.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog1], [0],
+[LOW-VALUE: 064 HIGH-VALUE: 193
+LOW-VALUE OK
+HIGH-VALUE OK
+X > LOW-VALUE
+X < HIGH-VALUE
+], [])
+
+AT_DATA([prog2.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog.
+       ENVIRONMENT DIVISION.
+       CONFIGURATION SECTION.
+       OBJECT-COMPUTER. x86,
+           PROGRAM COLLATING SEQUENCE IS alpha-custom.
+       SPECIAL-NAMES.
+           ALPHABET alpha-custom IS
+               65.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 LV-ORD PIC 999.
+       01 LV     PIC X.
+       88 IS-LV VALUE LOW-VALUE.
+       01 HV-ORD PIC 999.
+       01 HV     PIC X.
+       88 IS-HV VALUE HIGH-VALUE.
+       PROCEDURE DIVISION.
+           MOVE LOW-VALUE TO LV.
+           MOVE HIGH-VALUE TO HV.
+           MOVE FUNCTION ORD (LOW-VALUE) TO LV-ORD.
+           MOVE FUNCTION ORD (HIGH-VALUE) TO HV-ORD.
+           DISPLAY "LOW-VALUE: " LV-ORD
+                 " HIGH-VALUE: " HV-ORD.
+           IF LV = LOW-VALUE AND IS-LV
+             DISPLAY "LOW-VALUE OK"
+           ELSE
+             DISPLAY "LOW-VALUE KO"
+           END-IF.
+           IF HV = HIGH-VALUE AND IS-HV
+             DISPLAY "HIGH-VALUE OK"
+           ELSE
+             DISPLAY "HIGH-VALUE KO"
+           END-IF.
+           IF "X" > LOW-VALUE AND "X" > LV
+              DISPLAY "X > LOW-VALUE"
+           ELSE
+              DISPLAY "X < LOW-VALUE"
+           END-IF.
+           IF "X" < HIGH-VALUE AND "X" < HV
+              DISPLAY "X < HIGH-VALUE"
+           ELSE
+              DISPLAY "X > HIGH-VALUE"
+           END-IF.
+           STOP RUN.
+])
+
+AT_CHECK([$COMPILE prog2.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog2], [0],
+[LOW-VALUE: 065 HIGH-VALUE: 256
+LOW-VALUE OK
+HIGH-VALUE OK
+X > LOW-VALUE
+X < HIGH-VALUE
+], [])
+
+AT_DATA([prog3.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog.
+       ENVIRONMENT DIVISION.
+       CONFIGURATION SECTION.
+       OBJECT-COMPUTER. x86,
+           PROGRAM COLLATING SEQUENCE IS alpha-ebcdic.
+       SPECIAL-NAMES.
+           ALPHABET alpha-ebcdic IS EBCDIC.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 LV-ORD PIC 999.
+       01 LV     PIC X.
+       88 IS-LV VALUE LOW-VALUE.
+       01 HV-ORD PIC 999.
+       01 HV     PIC X.
+       88 IS-HV VALUE HIGH-VALUE.
+       PROCEDURE DIVISION.
+           MOVE LOW-VALUE TO LV.
+           MOVE HIGH-VALUE TO HV.
+           MOVE FUNCTION ORD (LOW-VALUE) TO LV-ORD.
+           MOVE FUNCTION ORD (HIGH-VALUE) TO HV-ORD.
+           DISPLAY "LOW-VALUE: " LV-ORD
+                 " HIGH-VALUE: " HV-ORD.
+           IF LV = LOW-VALUE AND IS-LV
+             DISPLAY "LOW-VALUE OK"
+           ELSE
+             DISPLAY "LOW-VALUE KO"
+           END-IF.
+           IF HV = HIGH-VALUE AND IS-HV
+             DISPLAY "HIGH-VALUE OK"
+           ELSE
+             DISPLAY "HIGH-VALUE KO"
+           END-IF.
+           IF "X" > LOW-VALUE AND "X" > LV
+              DISPLAY "X > LOW-VALUE"
+           ELSE
+              DISPLAY "X < LOW-VALUE"
+           END-IF.
+           IF "X" < HIGH-VALUE AND "X" < HV
+              DISPLAY "X < HIGH-VALUE"
+           ELSE
+              DISPLAY "X > HIGH-VALUE"
+           END-IF.
+           STOP RUN.
+])
+
+AT_CHECK([$COMPILE -febcdic-table=ebcdic500_latin1 prog3.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog3], [0],
+[LOW-VALUE: 001 HIGH-VALUE: 160
+LOW-VALUE OK
+HIGH-VALUE OK
+X > LOW-VALUE
+X < HIGH-VALUE
+], [])
+
+AT_DATA([prog4.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 LV-ORD PIC 999.
+       01 LV     PIC X.
+       88 IS-LV VALUE LOW-VALUE.
+       01 HV-ORD PIC 999.
+       01 HV     PIC X.
+       88 IS-HV VALUE HIGH-VALUE.
+       PROCEDURE DIVISION.
+           MOVE LOW-VALUE TO LV.
+           MOVE HIGH-VALUE TO HV.
+           MOVE FUNCTION ORD (LOW-VALUE) TO LV-ORD.
+           MOVE FUNCTION ORD (HIGH-VALUE) TO HV-ORD.
+           DISPLAY "LOW-VALUE: " LV-ORD
+                 " HIGH-VALUE: " HV-ORD.
+           IF LV = LOW-VALUE AND IS-LV
+             DISPLAY "LOW-VALUE OK"
+           ELSE
+             DISPLAY "LOW-VALUE KO"
+           END-IF.
+           IF HV = HIGH-VALUE AND IS-HV
+             DISPLAY "HIGH-VALUE OK"
+           ELSE
+             DISPLAY "HIGH-VALUE KO"
+           END-IF.
+           IF "X" > LOW-VALUE AND "X" > LV
+              DISPLAY "X > LOW-VALUE"
+           ELSE
+              DISPLAY "X < LOW-VALUE"
+           END-IF.
+           IF "X" < HIGH-VALUE AND "X" < HV
+              DISPLAY "X < HIGH-VALUE"
+           ELSE
+              DISPLAY "X > HIGH-VALUE"
+           END-IF.
+           STOP RUN.
+])
+
+AT_CHECK([$COMPILE -fdefault-colseq=EBCDIC -febcdic-table=ebcdic500_latin1 prog4.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog4], [0],
+[LOW-VALUE: 001 HIGH-VALUE: 160
+LOW-VALUE OK
+HIGH-VALUE OK
+X > LOW-VALUE
+X < HIGH-VALUE
+], [])
+
+AT_DATA([prog5.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog1.
+       ENVIRONMENT DIVISION.
+       CONFIGURATION SECTION.
+       OBJECT-COMPUTER. x86,
+           PROGRAM COLLATING SEQUENCE IS alpha-ebcdic.
+       SPECIAL-NAMES.
+           ALPHABET alpha-ebcdic IS EBCDIC.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 LV-ORD PIC 999.
+       01 LV     PIC X.
+       88 IS-LV VALUE LOW-VALUE.
+       01 HV-ORD PIC 999.
+       01 HV     PIC X.
+       88 IS-HV VALUE HIGH-VALUE.
+       PROCEDURE DIVISION.
+           MOVE LOW-VALUE TO LV.
+           MOVE HIGH-VALUE TO HV.
+           MOVE FUNCTION ORD (LOW-VALUE) TO LV-ORD.
+           MOVE FUNCTION ORD (HIGH-VALUE) TO HV-ORD.
+           DISPLAY "P1 LOW-VALUE: " LV-ORD
+                 " HIGH-VALUE: " HV-ORD.
+           IF LV = LOW-VALUE AND IS-LV
+             DISPLAY "LOW-VALUE OK"
+           ELSE
+             DISPLAY "LOW-VALUE KO"
+           END-IF.
+           IF HV = HIGH-VALUE AND IS-HV
+             DISPLAY "HIGH-VALUE OK"
+           ELSE
+             DISPLAY "HIGH-VALUE KO"
+           END-IF.
+           IF "X" > LOW-VALUE AND "X" > LV
+              DISPLAY "X > LOW-VALUE"
+           ELSE
+              DISPLAY "X < LOW-VALUE"
+           END-IF.
+           IF "X" < HIGH-VALUE AND "X" < HV
+              DISPLAY "X < HIGH-VALUE"
+           ELSE
+              DISPLAY "X > HIGH-VALUE"
+           END-IF.
+           CALL "prog2".
+           STOP RUN.
+       END PROGRAM prog1.
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog2.
+       ENVIRONMENT DIVISION.
+       CONFIGURATION SECTION.
+       OBJECT-COMPUTER. x86,
+           PROGRAM COLLATING SEQUENCE IS alpha-ascii.
+       SPECIAL-NAMES.
+           ALPHABET alpha-ascii IS ASCII.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 LV-ORD PIC 999.
+       01 LV     PIC X.
+       88 IS-LV VALUE LOW-VALUE.
+       01 HV-ORD PIC 999.
+       01 HV     PIC X.
+       88 IS-HV VALUE HIGH-VALUE.
+       PROCEDURE DIVISION.
+           MOVE LOW-VALUE TO LV.
+           MOVE HIGH-VALUE TO HV.
+           MOVE FUNCTION ORD (LOW-VALUE) TO LV-ORD.
+           MOVE FUNCTION ORD (HIGH-VALUE) TO HV-ORD.
+           DISPLAY "P2 LOW-VALUE: " LV-ORD
+                 " HIGH-VALUE: " HV-ORD.
+           IF LV = LOW-VALUE AND IS-LV
+             DISPLAY "LOW-VALUE OK"
+           ELSE
+             DISPLAY "LOW-VALUE KO"
+           END-IF.
+           IF HV = HIGH-VALUE AND IS-HV
+             DISPLAY "HIGH-VALUE OK"
+           ELSE
+             DISPLAY "HIGH-VALUE KO"
+           END-IF.
+           IF "X" > LOW-VALUE AND "X" > LV
+              DISPLAY "X > LOW-VALUE"
+           ELSE
+              DISPLAY "X < LOW-VALUE"
+           END-IF.
+           IF "X" < HIGH-VALUE AND "X" < HV
+              DISPLAY "X < HIGH-VALUE"
+           ELSE
+              DISPLAY "X > HIGH-VALUE"
+           END-IF.
+           STOP RUN.
+       END PROGRAM prog2.
+])
+
+AT_CHECK([$COMPILE -febcdic-table=ebcdic500_latin1 prog5.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog5], [0],
+[P1 LOW-VALUE: 001 HIGH-VALUE: 160
+LOW-VALUE OK
+HIGH-VALUE OK
+X > LOW-VALUE
+X < HIGH-VALUE
+P2 LOW-VALUE: 001 HIGH-VALUE: 256
+LOW-VALUE OK
+HIGH-VALUE OK
+X > LOW-VALUE
+X < HIGH-VALUE
+], [])
+
+AT_DATA([prog6.cob], [
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. prog.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       01 IND PIC 9(02).
+       01 ENDX PIC X(01).
+       01 ENDXS PIC X(05).
+       PROCEDURE DIVISION.
+           INITIALIZE ENDX.
+           PERFORM VARYING IND FROM 1 BY 1 UNTIL ENDX = HIGH-VALUE
+              DISPLAY IND " " WITH NO ADVANCING
+              IF IND = 9
+                 MOVE HIGH-VALUE TO ENDX
+              END-IF
+           END-PERFORM.
+           INITIALIZE ENDXS.
+           PERFORM VARYING IND FROM 1 BY 1 UNTIL ENDXS = HIGH-VALUE
+              DISPLAY IND " " WITH NO ADVANCING
+              IF IND = 9
+                 MOVE HIGH-VALUE TO ENDXS
+              END-IF
+           END-PERFORM.
+           STOP RUN.
+])
+
+AT_CHECK([$COMPILE -fdefault-colseq=EBCDIC -febcdic-table=ebcdic500_latin1 prog6.cob], [0], [], [])
+AT_CHECK([$COBCRUN_DIRECT ./prog6], [0],
+[01 02 03 04 05 06 07 08 09 01 02 03 04 05 06 07 08 09 ], [])
+
+AT_CLEANUP
diff --git a/tests/testsuite.src/syn_literals.at b/tests/testsuite.src/syn_literals.at
index f4d8f8a5d..ea9d3d7da 100644
--- a/tests/testsuite.src/syn_literals.at
+++ b/tests/testsuite.src/syn_literals.at
@@ -1556,7 +1556,7 @@ AT_CHECK([$COMPILE prog2.cob], [0], [],
 ])
 AT_CHECK([$COMPILE -febcdic-symbolic-characters -febcdic-table=dummyNotThere prog2.cob], [1], [],
 [libcob: error: can't open translation table 'dummyNotThere'
-prog2.cob:5: error: invalid parameter: -febcdic-table
+cobc: error: invalid parameter: -febcdic-table
 ])
 
 AT_CLEANUP