Change int8_t to signed char on Solaris [PR113450,PR123176]

int8_t is currently defined as char in Solaris <sys/int_types.h>

/*
 * Basic / Extended integer types
 *
 * The following defines the basic fixed-size integer types.
 *
 * Implementations are free to typedef them to Standard C integer types or
 * extensions that they support. If an implementation does not support one
 * of the particular integer data types below, then it should not define the
 * typedefs and macros corresponding to that data type.  Note that int8_t
 * is not defined in -Xs mode on ISAs for which the ABI specifies "char"
 * as an unsigned entity because there is no way to define an eight bit
 * signed integral.
 */
typedef char			int8_t;
typedef signed char		int8_t;

and _CHAR_IS_SIGNED defined as 1 in <sys/isa_defs.h>.  As has long been
known, this violates C99, 7.18.1.1, Exact-width integer types.

While this works in general nonetheless, it creates constant trouble for
C++ code as can be seen in PRs libstdc++/113450 and recently
libstdc++/123176, but also in LLVM.

While Oracle Solaris engineering is amenable to changing int8_t to
signed char, this will take time.  However, it proved easy to do so now
using fixincludes.

This works for a GCC bootstrap just fine with one exception: as
documented in PR d/123509, libdruntime has its own definition of int8_t
which is now inconsistent with GCC's.  This leads to some gdc.test and
libphobos testsuite failures, which can easily be fixed with the patch
attached to that PR.  I wouldn't consider this a showstopper for GCC 16
if that patch wouldn't make it to the release.

However, the failures point to another problem: with this change, the
mangling of

	void func(int8_t);

changes in C++, creating an ABI break.  Fortunately, this isn't seen in
libstdc++, so the impact should be reasonable compared to the constant
trouble the current definition causes for C++.

Besides, clang already uses

	#define __INT8_TYPE__ signed char

apparently without problems.

In case users do run into the incompatiblity, the fixed definitions are
wrapped in #if !defined(_LEGACY_INT8_T)/#endif so there's an easy way back
to the original definition.

Bootstrapped on i386-pc-solaris2.11, amd64-pc-solaris2.11,
sparc-sun-solaris2.11, and sparcv9-sun-solaris2.11 with only the D
failure described above.

I've also run 1-stage and bootstrap builds of LLVM main using a patched
GCC 16 as bootstrap compiler on amd64-pc-solaris2.11 and
sparcv9-sun-solaris2.11 without regressions.

2026-01-07  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	fixincludes:
	PR libstdc++/113450
	PR libstdc++/123176
	* inclhack.def (solaris_int8_t): New fix.
	* fixincl.x: Regenerate.

	gcc:
	PR libstdc++/113450
	PR libstdc++/123176
	* config/sol2.h (INT8_TYPE): Change to signed char.
	(INT_LEAST8_TYPE): Likewise.
	(INT_FAST8_TYPE): Likewise.

diff --git a/fixincludes/fixincl.x b/fixincludes/fixincl.x
index 6f2c1ffbefe834f3888951fd8fe1a4beab30564e..9db4d376a2e3df2b2f12c74dda6b37e06df49c93 100644 (file)
--- a/fixincludes/fixincl.x
+++ b/fixincludes/fixincl.x
@@ -2,11 +2,11 @@
  *
  * DO NOT EDIT THIS FILE   (fixincl.x)
  *
- * It has been AutoGen-ed  January  6, 2026 at 04:43:53 PM by AutoGen 5.18.12
+ * It has been AutoGen-ed  February 15, 2026 at 11:11:08 PM by AutoGen 5.18.12
  * From the definitions    inclhack.def
  * and the template file   fixincl
  */
-/* DO NOT MERGE THIS FILE, EITHER Tue Jan  6 16:43:53 CET 2026
+/* DO NOT MERGE THIS FILE, EITHER Sun Feb 15 23:11:08 CET 2026
  *
  * You must regenerate it.  Use the ./genfixes script.
  *
@@ -15,7 +15,7 @@
  * certain ANSI-incompatible system header files which are fixed to work
  * correctly with ANSI C and placed in a directory that GNU C will search.
  *
- * This file contains 250 fixup descriptions.
+ * This file contains 251 fixup descriptions.
  *
  * See README for more information.
  *
@@ -7869,6 +7869,54 @@ static const char* apzSolaris_Int_Limits_3Patch[] = {
     "#define\tSIZE_MAX\t4294967295U",
     (char*)NULL };
 
+/* * * * * * * * * * * * * * * * * * * * * * * * * *
+ *
+ *  Description of Solaris_Int8_T fix
+ */
+tSCC zSolaris_Int8_TName[] =
+     "solaris_int8_t";
+
+/*
+ *  File name selection pattern
+ */
+tSCC zSolaris_Int8_TList[] =
+  "sys/int_types.h\0";
+/*
+ *  Machine/OS name selection pattern
+ */
+tSCC* apzSolaris_Int8_TMachs[] = {
+        "*-*-solaris2*",
+        (const char*)NULL };
+
+/*
+ *  content selection pattern - do fix if pattern found
+ */
+tSCC zSolaris_Int8_TSelect0[] =
+       "^[ \t]*typedef[ \t]*char[ \t]*int(|_fast|_least)8_t.*";
+
+/*
+ *  content bypass pattern - skip fix if pattern found
+ */
+tSCC zSolaris_Int8_TBypass0[] =
+       "_LEGACY_INT8_T";
+
+#define    SOLARIS_INT8_T_TEST_CT  2
+static tTestDesc aSolaris_Int8_TTests[] = {
+  { TT_NEGREP,   zSolaris_Int8_TBypass0, (regex_t*)NULL },
+  { TT_EGREP,    zSolaris_Int8_TSelect0, (regex_t*)NULL }, };
+
+/*
+ *  Fix Command Arguments for Solaris_Int8_T
+ */
+static const char* apzSolaris_Int8_TPatch[] = {
+    "format",
+    "#if !defined(_LEGACY_INT8_T)\n\
+typedef signed char int%18_t;\n\
+#else\n\
+%0\n\
+#endif",
+    (char*)NULL };
+
 /* * * * * * * * * * * * * * * * * * * * * * * * * *
  *
  *  Description of Solaris_Math_12 fix
@@ -10235,9 +10283,9 @@ static const char* apzX11_SprintfPatch[] = {
  *
  *  List of all fixes
  */
-#define REGEX_COUNT          289
+#define REGEX_COUNT          291
 #define MACH_LIST_SIZE_LIMIT 187
-#define FIX_COUNT            250
+#define FIX_COUNT            251
 
 /*
  *  Enumerate the fixes
@@ -10434,6 +10482,7 @@ typedef enum {
     SOLARIS_INT_CONST_FIXIDX,
     SOLARIS_INT_LIMITS_1_FIXIDX,
     SOLARIS_INT_LIMITS_3_FIXIDX,
+    SOLARIS_INT8_T_FIXIDX,
     SOLARIS_MATH_12_FIXIDX,
     SOLARIS_POW_INT_OVERLOAD_FIXIDX,
     STATSSWTCH_FIXIDX,
@@ -11451,6 +11500,11 @@ tFixDesc fixDescList[ FIX_COUNT ] = {
      SOLARIS_INT_LIMITS_3_TEST_CT, FD_MACH_ONLY | FD_SUBROUTINE,
      aSolaris_Int_Limits_3Tests,   apzSolaris_Int_Limits_3Patch, 0 },
 
+  {  zSolaris_Int8_TName,    zSolaris_Int8_TList,
+     apzSolaris_Int8_TMachs,
+     SOLARIS_INT8_T_TEST_CT, FD_MACH_ONLY | FD_SUBROUTINE,
+     aSolaris_Int8_TTests,   apzSolaris_Int8_TPatch, 0 },
+
   {  zSolaris_Math_12Name,    zSolaris_Math_12List,
      apzSolaris_Math_12Machs,
      SOLARIS_MATH_12_TEST_CT, FD_MACH_ONLY,

diff --git a/fixincludes/inclhack.def b/fixincludes/inclhack.def
index 53022aaeee563b485dd0a3f128ed9a42832d3609..91f29a2ca7ce0670dbaa71e75aea5e36b400afdf 100644 (file)
--- a/fixincludes/inclhack.def
+++ b/fixincludes/inclhack.def
@@ -3930,6 +3930,28 @@ fix = {
     "#define   SIZE_MAX        4294967295UL";
 };
 
+/*
+ * Solaris <sys/int_types.h> defines int8_t as char which violates C99.
+ * Same for int_fast8_t and int_least8_t.
+ */
+fix = {
+    hackname  = solaris_int8_t;
+    files     = sys/int_types.h;
+    mach      = '*-*-solaris2*';
+    bypass    = '_LEGACY_INT8_T';
+    c_fix     = format;
+    c_fix_arg = "#if !defined(_LEGACY_INT8_T)\n"
+                "typedef signed char int%18_t;\n"
+                "#else\n"
+                "%0\n"
+                "#endif";
+    select    = "^[ \t]*typedef[ \t]*char[ \t]*int(|_fast|_least)8_t.*";
+    test_text =
+    "typedef char int8_t;\n"
+    "typedef char int_fast8_t;\n"
+    "typedef char int_least8_t;";
+};
+
 /*
  * Some versions of Solaris 10+ <math.h> #undef libstdc++-internal macros.
  */

diff --git a/fixincludes/tests/base/sys/int_types.h b/fixincludes/tests/base/sys/int_types.h
new file mode 100644 (file)
index 0000000..dcde665
--- /dev/null
+++ b/fixincludes/tests/base/sys/int_types.h
@@ -0,0 +1,28 @@
+/*  DO NOT EDIT THIS FILE.
+
+    It has been auto-edited by fixincludes from:
+
+       "fixinc/tests/inc/sys/int_types.h"
+
+    This had to be done to correct non-standard usages in the
+    original, manufacturer supplied header file.  */
+
+
+
+#if defined( SOLARIS_INT8_T_CHECK )
+#if !defined(_LEGACY_INT8_T)
+typedef signed char int8_t;
+#else
+typedef char int8_t;
+#endif
+#if !defined(_LEGACY_INT8_T)
+typedef signed char int_fast8_t;
+#else
+typedef char int_fast8_t;
+#endif
+#if !defined(_LEGACY_INT8_T)
+typedef signed char int_least8_t;
+#else
+typedef char int_least8_t;
+#endif
+#endif  /* SOLARIS_INT8_T_CHECK */

diff --git a/gcc/config/sol2.h b/gcc/config/sol2.h
index 489c650495fb6f1583273a6a14be8785daffef64..398aa383505abc9684514106c0a55ccc856e6e75 100644 (file)
--- a/gcc/config/sol2.h
+++ b/gcc/config/sol2.h
@@ -49,9 +49,11 @@ along with GCC; see the file COPYING3.  If not see
 
 #define SIG_ATOMIC_TYPE "int"
 
-/* ??? This definition of int8_t follows the system header but does
-   not conform to C99.  Likewise int_fast8_t, int_least8_t.  */
-#define INT8_TYPE "char"
+/* <sys/int_types.h> uses char (which is signed) to define int8_t, which does
+   not conform to C99, 7.18.1.1 Exact-width integer types.  Likewise
+   int_fast8_t, int_least8_t.  Until this is fixed, it's handled by
+   fixincludes.  */
+#define INT8_TYPE "signed char"
 #define INT16_TYPE "short int"
 #define INT32_TYPE "int"
 #define INT64_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "long long int")
@@ -60,7 +62,7 @@ along with GCC; see the file COPYING3.  If not see
 #define UINT32_TYPE "unsigned int"
 #define UINT64_TYPE (LONG_TYPE_SIZE == 64 ? "long unsigned int" : "long long unsigned int")
 
-#define INT_LEAST8_TYPE "char"
+#define INT_LEAST8_TYPE "signed char"
 #define INT_LEAST16_TYPE "short int"
 #define INT_LEAST32_TYPE "int"
 #define INT_LEAST64_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "long long int")
@@ -69,7 +71,7 @@ along with GCC; see the file COPYING3.  If not see
 #define UINT_LEAST32_TYPE "unsigned int"
 #define UINT_LEAST64_TYPE (LONG_TYPE_SIZE == 64 ? "long unsigned int" : "long long unsigned int")
 
-#define INT_FAST8_TYPE "char"
+#define INT_FAST8_TYPE "signed char"
 #define INT_FAST16_TYPE "int"
 #define INT_FAST32_TYPE "int"
 #define INT_FAST64_TYPE (LONG_TYPE_SIZE == 64 ? "long int" : "long long int")