[libc-commits] [libc] a439c4a - [libc][Obvious] Address few GCC warnings.

[Siva Chandra Reddy via libc-commits]

Author: Siva Chandra Reddy
Date: 2023-01-09T20:54:13Z
New Revision: a439c4afdc4f6e24f8cbed0aa10820e2fe48317c

URL: https://github.com/llvm/llvm-project/commit/a439c4afdc4f6e24f8cbed0aa10820e2fe48317c
DIFF: https://github.com/llvm/llvm-project/commit/a439c4afdc4f6e24f8cbed0aa10820e2fe48317c.diff

LOG: [libc][Obvious] Address few GCC warnings.

Added: 
    

Modified: 
    libc/src/__support/arg_list.h
    libc/src/__support/float_to_string.h
    libc/src/math/generic/log10.cpp
    libc/src/stdio/printf_core/converter_utils.h
    libc/src/stdio/stderr.cpp
    libc/src/stdio/stdin.cpp
    libc/src/stdio/stdout.cpp
    libc/src/unistd/environ.cpp
    libc/src/unistd/getopt.cpp
    libc/startup/linux/x86_64/start.cpp

Removed: 
    


################################################################################
diff  --git a/libc/src/__support/arg_list.h b/libc/src/__support/arg_list.h
index 3a885df6495ea..4d82b5e5b2aee 100644
--- a/libc/src/__support/arg_list.h
+++ b/libc/src/__support/arg_list.h
@@ -22,6 +22,11 @@ class ArgList {
   ArgList(ArgList &other) { va_copy(this->vlist, other.vlist); }
   ~ArgList() { va_end(this->vlist); }
 
+  ArgList &operator=(ArgList &rhs) {
+    va_copy(vlist, rhs.vlist);
+    return *this;
+  }
+
   template <class T> T inline next_var() { return va_arg(vlist, T); }
 };
 

diff  --git a/libc/src/__support/float_to_string.h b/libc/src/__support/float_to_string.h
index da1defa7646a3..b7b1d38070ab2 100644
--- a/libc/src/__support/float_to_string.h
+++ b/libc/src/__support/float_to_string.h
@@ -359,8 +359,8 @@ constexpr size_t FloatToString<long double>::zero_blocks_after_point() {
 }
 
 template <>
-constexpr bool FloatToString<long double>::is_lowest_block(size_t block_index) {
-  return block_index < 0;
+constexpr bool FloatToString<long double>::is_lowest_block(size_t) {
+  return false;
 }
 
 template <>

diff  --git a/libc/src/math/generic/log10.cpp b/libc/src/math/generic/log10.cpp
index 3ce634baf89e3..dbc9f80448c27 100644
--- a/libc/src/math/generic/log10.cpp
+++ b/libc/src/math/generic/log10.cpp
@@ -914,13 +914,11 @@ double log10_accurate(int e_x, int index, double m_x) {
   fputil::DoubleDouble mx{/*lo*/ 0.0, /*hi*/ m_x};
 
   // Further range reductions.
-  int idx[R_STEPS];
   double scale = 0x1.0p+7;
   const fputil::DyadicFloat<128> NEG_ONE(-1.0);
   for (size_t i = 0; i < R_STEPS; ++i) {
     scale *= 0x1.0p+4;
     int id = static_cast<int>(fputil::multiply_add(mx.hi, scale, 0x1.0p+4));
-    idx[i] = id;
     double r = RR[i][id];
     fputil::DoubleDouble rm = fputil::exact_mult(r, mx.hi);
     rm.hi += r - 1.0;

diff  --git a/libc/src/stdio/printf_core/converter_utils.h b/libc/src/stdio/printf_core/converter_utils.h
index ec605abf7deb8..4d2c84700ad37 100644
--- a/libc/src/stdio/printf_core/converter_utils.h
+++ b/libc/src/stdio/printf_core/converter_utils.h
@@ -41,6 +41,7 @@ inline uintmax_t apply_length_modifier(uintmax_t num, LengthModifier lm) {
   case LengthModifier::j:
     return num; // j is intmax, so no mask is necessary.
   }
+  __builtin_unreachable();
 }
 
 #define RET_IF_RESULT_NEGATIVE(func)                                           \

diff  --git a/libc/src/stdio/stderr.cpp b/libc/src/stdio/stderr.cpp
index e3ceae94aa242..56ec9b78a67f0 100644
--- a/libc/src/stdio/stderr.cpp
+++ b/libc/src/stdio/stderr.cpp
@@ -10,4 +10,6 @@
 
 #include <stdio.h>
 
-extern "C" FILE *stderr = reinterpret_cast<FILE *>(__llvm_libc::stderr);
+extern "C" {
+FILE *stderr = reinterpret_cast<FILE *>(__llvm_libc::stderr);
+}

diff  --git a/libc/src/stdio/stdin.cpp b/libc/src/stdio/stdin.cpp
index cd34189c4b115..b6ae95d32ff40 100644
--- a/libc/src/stdio/stdin.cpp
+++ b/libc/src/stdio/stdin.cpp
@@ -10,4 +10,6 @@
 
 #include <stdio.h>
 
-extern "C" FILE *stdin = reinterpret_cast<FILE *>(__llvm_libc::stdin);
+extern "C" {
+FILE *stdin = reinterpret_cast<FILE *>(__llvm_libc::stdin);
+}

diff  --git a/libc/src/stdio/stdout.cpp b/libc/src/stdio/stdout.cpp
index c64275a0a952c..7eb9e1bf8e735 100644
--- a/libc/src/stdio/stdout.cpp
+++ b/libc/src/stdio/stdout.cpp
@@ -10,4 +10,6 @@
 
 #include <stdio.h>
 
-extern "C" FILE *stdout = reinterpret_cast<FILE *>(__llvm_libc::stdout);
+extern "C" {
+FILE *stdout = reinterpret_cast<FILE *>(__llvm_libc::stdout);
+}

diff  --git a/libc/src/unistd/environ.cpp b/libc/src/unistd/environ.cpp
index d3f6f4cca4712..2a554fd9fcb4c 100644
--- a/libc/src/unistd/environ.cpp
+++ b/libc/src/unistd/environ.cpp
@@ -9,6 +9,8 @@
 namespace __llvm_libc {
 
 // This is initialized to the correct value by the statup code.
-extern "C" char **environ = nullptr;
+extern "C" {
+char **environ = nullptr;
+}
 
 } // namespace __llvm_libc

diff  --git a/libc/src/unistd/getopt.cpp b/libc/src/unistd/getopt.cpp
index 9d3b53400560e..e68f906b3e270 100644
--- a/libc/src/unistd/getopt.cpp
+++ b/libc/src/unistd/getopt.cpp
@@ -170,10 +170,14 @@ int getopt_r(int argc, char *const argv[], const char *optstring,
 
 namespace impl {
 
-extern "C" char *optarg = nullptr;
-extern "C" int optind = 1;
-extern "C" int optopt = 0;
-extern "C" int opterr = 0;
+extern "C" {
+
+char *optarg = nullptr;
+int optind = 1;
+int optopt = 0;
+int opterr = 0;
+
+}
 
 static unsigned optpos;
 

diff  --git a/libc/startup/linux/x86_64/start.cpp b/libc/startup/linux/x86_64/start.cpp
index 6ddb344b339af..15d5de59d42c1 100644
--- a/libc/startup/linux/x86_64/start.cpp
+++ b/libc/startup/linux/x86_64/start.cpp
@@ -151,8 +151,8 @@ extern "C" void _start() {
   // compilers can generate code assuming the alignment as required by the ABI.
   // If the stack pointers as setup by the OS are already aligned, then the
   // following code is a NOP.
-  __asm__ __volatile__("andq $0xfffffffffffffff0, %%rsp\n\t" ::: "%rsp");
-  __asm__ __volatile__("andq $0xfffffffffffffff0, %%rbp\n\t" ::: "%rbp");
+  __asm__ __volatile__("andq $0xfffffffffffffff0, %rsp\n\t");
+  __asm__ __volatile__("andq $0xfffffffffffffff0, %rbp\n\t");
 
   auto tid = __llvm_libc::syscall_impl(SYS_gettid);
   if (tid <= 0)